```

                                                             OMB APPROVAL
                                                     OMB Number:       3235-0578
                                                     Expires:  January 31, 2016
                                                     Estimated average burden
                                                     hours per response.....
                                                     10.5

                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM N-Q

                   QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS
    OF REGISTERED MANAGEMENT INVESTMENT COMPANY

  Investment Company Act file number 811-21664

                         Pioneer Series Trust III
               (Exact name of registrant as specified in charter)

                       60 State Street, Boston, MA 02109
              (Address of principal executive offices) (ZIP code)

            Terrence J. Cullen, Pioneer Investment Management, Inc.,
                       60 State Street, Boston, MA 02109
                    (Name and address of agent for service)

Registrant's telephone number, including area code:  (617) 742-7825

Date of fiscal year end:  August 31

Date of reporting period:  May 31, 2015

Form N-Q is to be used by management investment companies, other than small
business investment companies registered on Form N-5 (239.24 and 274.5 of this
chapter), to file reports with the Commission, not later than 60 days after
close of the first and third fiscal quarters, pursuant to Rule 30b1-5 under
the Investment Company Act of 1940 (17 CFR 270.30b1-5).  The Commission may
use the information provided on Form N-Q in its regulatory, disclosure review,
inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-Q,
and the Commission will make this information public. A registrant is not
required to respond to the collection of information contained in Form N-Q
unless the Form displays a currently valid Office of Management and Budget
("OMB") control number. Please direct comments concerning the accuracy of the
information collection burden estimate and any suggestions for reducing the
burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW,
Washington, DC 20549-0609.  The OMB has reviewed this collection of information
under the clearance requirements of 44 U.S.C. ss. 3507.

<PAGE>
ITEM 1. Schedule of Investments.

File the schedules as of the close of the reporting period as set forth in
ss. 210.12-12  12-14 of Regulation S-X [17 CFR 210.12-12  12-14]. The
schedules need not be audited.
```

```

```

|                                                                                                                                                             |      |   |   | Pioneer Disciplined Value Fund                                                                                                                |   |                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------|--------|--------|-----------------------------------------------------------------------------------------------------------------------------------------------|--------|-------------------------------------------------------------------------------|
|                                                                                                                                                             |      |   |   | Schedule of Investments 5/29/15 (unaudited)                                                                                                   |   |                                                                          |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             | Shares    |   |   |                                                                                                                                          |   | Value                                                                         |
|                                                                                                                                                             |      |   |   | COMMON STOCKS - 99.6%                                                                                                                         |   |                                                                          |
|                                                                                                                                                             |      |   |   | Energy - 10.8%                                                                                                                                |   |                                                                          |
|                                                                                                                                                             |      |   |   | Integrated Oil & Gas - 5.6%                                                                                                               |   |                                                                          |
|                                                                                                                                                             | 263,269   |   |   | Exxon Mobil Corp.                                                                                                                             | $      | 22,430,519                                                                    |
|                                                                                                                                                             | 324,009   |   |   | Occidental Petroleum Corp.                                                                                                                    |   | 25,334,264                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 47,764,783                                                                    |
|                                                                                                                                                             |      |   |   | Oil & Gas Exploration & Production - 5.2%                                                                                             |   |                                                                          |
|                                                                                                                                                             | 351,329   |   |   | ConocoPhillips                                                                                                                                | $      | 22,372,631                                                                    |
|                                                                                                                                                             | 347,490   |   |   | Devon Energy Corp.                                                                                                                            |   | 22,663,298                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 45,035,929                                                                    |
|                                                                                                                                                             |      |   |   | Total Energy                                                                                                                                  | $      | 92,800,712                                                                    |
|                                                                                                                                                             |      |   |   | Materials - 2.0%                                                                                                                              |   |                                                                          |
|                                                                                                                                                             |      |   |   | Paper Products - 2.0%                                                                                                                         |   |                                                                          |
|                                                                                                                                                             | 324,222   |   |   | International Paper Co.                                                                                                                       | $      | 16,804,426                                                                    |
|                                                                                                                                                             |      |   |   | Total Materials                                                                                                                               | $      | 16,804,426                                                                    |
|                                                                                                                                                             |      |   |   | Capital Goods - 6.0%                                                                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | Electrical Components & Equipment - 2.1%                                                                                                  |   |                                                                          |
|                                                                                                                                                             | 246,252   |   |   | Eaton Corp. Plc                                                                                                                               | $      | 17,629,181                                                                    |
|                                                                                                                                                             |      |   |   | Industrial Conglomerates - 2.9%                                                                                                               |   |                                                                          |
|                                                                                                                                                             | 924,383   |   |   | General Electric Co.                                                                                                                          | $      | 25,207,924                                                                    |
|                                                                                                                                                             |      |   |   | Construction & Farm Machinery & Heavy Trucks - 1.0%                                                                                   |   |                                                                          |
|                                                                                                                                                             | 65,772    |   |   | Cummins, Inc.                                                                                                                                 | $      | 8,915,395                                                                     |
|                                                                                                                                                             |      |   |   | Total Capital Goods                                                                                                                           | $      | 51,752,500                                                                    |
|                                                                                                                                                             |      |   |   | Transportation - 2.2%                                                                                                                         |   |                                                                          |
|                                                                                                                                                             |      |   |   | Airlines - 2.2%                                                                                                                               |   |                                                                          |
|                                                                                                                                                             | 216,596   |   |   | American Airlines Group, Inc.                                                                                                                 | $      | 9,177,173                                                                     |
|                                                                                                                                                             | 173,356   |   |   | United Continental Holdings, Inc. *                                                                                                           |   | 9,463,504                                                                     |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 18,640,677                                                                    |
|                                                                                                                                                             |      |   |   | Total Transportation                                                                                                                          | $      | 18,640,677                                                                    |
|                                                                                                                                                             |      |   |   | Automobiles & Components - 2.9%                                                                                                           |   |                                                                          |
|                                                                                                                                                             |      |   |   | Automobile Manufacturers - 2.9%                                                                                                               |   |                                                                          |
|                                                                                                                                                             | 703,945   |   |   | General Motors Co. *                                                                                                                          | $      | 25,320,902                                                                    |
|                                                                                                                                                             |      |   |   | Total Automobiles & Components                                                                                                            | $      | 25,320,902                                                                    |
|                                                                                                                                                             |      |   |   | Consumer Durables & Apparel - 3.2%                                                                                                        |   |                                                                          |
|                                                                                                                                                             |      |   |   | Homebuilding - 1.3%                                                                                                                           |   |                                                                          |
|                                                                                                                                                             | 232,775   |   |   | Lennar Corp.                                                                                                                                  | $      | 10,854,298                                                                    |
|                                                                                                                                                             |      |   |   | Household Appliances - 1.9%                                                                                                                   |   |                                                                          |
|                                                                                                                                                             | 88,980    |   |   | Whirlpool Corp.                                                                                                                               | $      | 16,394,565                                                                    |
|                                                                                                                                                             |      |   |   | Total Consumer Durables & Apparel                                                                                                         | $      | 27,248,863                                                                    |
|                                                                                                                                                             |      |   |   | Media - 3.9%                                                                                                                                  |   |                                                                          |
|                                                                                                                                                             |      |   |   | Broadcasting - 2.4%                                                                                                                           |   |                                                                          |
|                                                                                                                                                             | 326,038   |   |   | CBS Corp. (Class B)                                                                                                                           | $      | 20,123,065                                                                    |
|                                                                                                                                                             |      |   |   | Movies & Entertainment - 1.5%                                                                                                             |   |                                                                          |
|                                                                                                                                                             | 197,827   |   |   | Viacom, Inc. (Class B)                                                                                                                        | $      | 13,230,670                                                                    |
|                                                                                                                                                             |      |   |   | Total Media                                                                                                                                   | $      | 33,353,735                                                                    |
|                                                                                                                                                             |      |   |   | Retailing - 1.6%                                                                                                                              |   |                                                                          |
|                                                                                                                                                             |      |   |   | Homefurnishing Retail - 1.6%                                                                                                                  |   |                                                                          |
|                                                                                                                                                             | 199,131   |   |   | Bed Bath & Beyond, Inc. *                                                                                                                 | $      | 14,202,023                                                                    |
|                                                                                                                                                             |      |   |   | Total Retailing                                                                                                                               | $      | 14,202,023                                                                    |
|                                                                                                                                                             |      |   |   | Food, Beverage & Tobacco - 7.1%                                                                                                           |   |                                                                          |
|                                                                                                                                                             |      |   |   | Brewers - 2.0%                                                                                                                                |   |                                                                          |
|                                                                                                                                                             | 229,620   |   |   | Molson Coors Brewing Co. (Class B)                                                                                                            | $      | 16,849,516                                                                    |
|                                                                                                                                                             |      |   |   | Agricultural Products - 1.7%                                                                                                                  |   |                                                                          |
|                                                                                                                                                             | 277,148   |   |   | Archer-Daniels-Midland Co.                                                                                                                    | $      | 14,647,272                                                                    |
|                                                                                                                                                             |      |   |   | Packaged Foods & Meats - 3.4%                                                                                                             |   |                                                                          |
|                                                                                                                                                             | 314,518   |   |   | ConAgra Foods, Inc.                                                                                                                           | $      | 12,143,540                                                                    |
|                                                                                                                                                             | 410,687   |   |   | Tyson Foods, Inc.                                                                                                                             |   | 17,433,663                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 29,577,203                                                                    |
|                                                                                                                                                             |      |   |   | Total Food, Beverage & Tobacco                                                                                                            | $      | 61,073,991                                                                    |
|                                                                                                                                                             |      |   |   | Health Care Equipment & Services - 7.7%                                                                                                   |   |                                                                          |
|                                                                                                                                                             |      |   |   | Health Care Services - 2.2%                                                                                                                   |   |                                                                          |
|                                                                                                                                                             | 215,067   |   |   | Express Scripts Holding Co. *                                                                                                                 | $      | 18,740,938                                                                    |
|                                                                                                                                                             |      |   |   | Health Care Facilities - 2.3%                                                                                                                 |   |                                                                          |
|                                                                                                                                                             | 244,956   |   |   | HCA Holdings, Inc.                                                                                                                            | $      | 20,044,749                                                                    |
|                                                                                                                                                             |      |   |   | Managed Health Care - 3.2%                                                                                                                    |   |                                                                          |
|                                                                                                                                                             | 230,096   |   |   | Aetna, Inc.                                                                                                                                   | $      | 27,144,425                                                                    |
|                                                                                                                                                             |      |   |   | Total Health Care Equipment & Services                                                                                                    | $      | 65,930,112                                                                    |
|                                                                                                                                                             |      |   |   | Pharmaceuticals, Biotechnology & Life Sciences - 9.4%                                                                                     |   |                                                                          |
|                                                                                                                                                             |      |   |   | Pharmaceuticals - 9.4%                                                                                                                        |   |                                                                          |
|                                                                                                                                                             | 194,525   |   |   | AbbVie, Inc.                                                                                                                                  | $      | 12,953,420                                                                    |
|                                                                                                                                                             | 106,155   |   |   | Mallinckrodt Plc *                                                                                                                            |   | 13,740,703                                                                    |
|                                                                                                                                                             | 290,726   |   |   | Merck & Co., Inc.                                                                                                                         |   | 17,702,306                                                                    |
|                                                                                                                                                             | 242,505   |   |   | Mylan NV                                                                                                                                      |   | 17,613,138                                                                    |
|                                                                                                                                                             | 310,224   |   |   | Teva Pharmaceutical Industries, Ltd. (A.D.R.)                                                                                                 |   | 18,644,462                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 80,654,029                                                                    |
|                                                                                                                                                             |      |   |   | Total Pharmaceuticals, Biotechnology & Life Sciences                                                                                      | $      | 80,654,029                                                                    |
|                                                                                                                                                             |      |   |   | Banks - 14.8%                                                                                                                                 |   |                                                                          |
|                                                                                                                                                             |      |   |   | Diversified Banks - 10.2%                                                                                                                     |   |                                                                          |
|                                                                                                                                                             | 1,111,038 |   |   | Bank of America Corp.                                                                                                                         | $      | 18,332,127                                                                    |
|                                                                                                                                                             | 478,264   |   |   | Citigroup, Inc.                                                                                                                               |   | 25,864,517                                                                    |
|                                                                                                                                                             | 405,592   |   |   | US Bancorp/MN                                                                                                                                 |   | 17,485,071                                                                    |
|                                                                                                                                                             | 467,237   |   |   | Wells Fargo & Co.                                                                                                                         |   | 26,146,583                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 87,828,298                                                                    |
|                                                                                                                                                             |      |   |   | Regional Banks - 4.6%                                                                                                                         |   |                                                                          |
|                                                                                                                                                             | 466,865   |   |   | Citizens Financial Group, Inc.                                                                                                                | $      | 12,530,657                                                                    |
|                                                                                                                                                             | 285,326   |   |   | The PNC Financial Services Group, Inc.                                                                                                        |   | 27,302,844                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 39,833,501                                                                    |
|                                                                                                                                                             |      |   |   | Total Banks                                                                                                                                   | $      | 127,661,799                                                                   |
|                                                                                                                                                             |      |   |   | Diversified Financials - 4.7%                                                                                                                 |   |                                                                          |
|                                                                                                                                                             |      |   |   | Specialized Finance - 1.1%                                                                                                                    |   |                                                                          |
|                                                                                                                                                             | 194,004   |   |   | The NASDAQ OMX Group, Inc.                                                                                                                    | $      | 10,039,707                                                                    |
|                                                                                                                                                             |      |   |   | Asset Management & Custody Banks - 1.4%                                                                                                   |   |                                                                          |
|                                                                                                                                                             | 296,487   |   |   | Invesco, Ltd.                                                                                                                                 | $      | 11,809,077                                                                    |
|                                                                                                                                                             |      |   |   | Investment Banking & Brokerage - 2.2%                                                                                                     |   |                                                                          |
|                                                                                                                                                             | 495,995   |   |   | Morgan Stanley Co.                                                                                                                            | $      | 18,947,009                                                                    |
|                                                                                                                                                             |      |   |   | Total Diversified Financials                                                                                                                  | $      | 40,795,793                                                                    |
|                                                                                                                                                             |      |   |   | Insurance - 4.2%                                                                                                                              |   |                                                                          |
|                                                                                                                                                             |      |   |   | Life & Health Insurance - 1.9%                                                                                                            |   |                                                                          |
|                                                                                                                                                             | 294,379   |   |   | Lincoln National Corp.                                                                                                                        | $      | 16,782,547                                                                    |
|                                                                                                                                                             |      |   |   | Multi-line Insurance - 2.3%                                                                                                                   |   |                                                                          |
|                                                                                                                                                             | 480,870   |   |   | The Hartford Financial Services Group, Inc.                                                                                                   | $      | 19,768,566                                                                    |
|                                                                                                                                                             |      |   |   | Total Insurance                                                                                                                               | $      | 36,551,113                                                                    |
|                                                                                                                                                             |      |   |   | Software & Services - 3.6%                                                                                                                |   |                                                                          |
|                                                                                                                                                             |      |   |   | Systems Software - 3.6%                                                                                                                       |   |                                                                          |
|                                                                                                                                                             | 331,234   |   |   | Microsoft Corp.                                                                                                                               | $      | 15,521,625                                                                    |
|                                                                                                                                                             | 354,015   |   |   | Oracle Corp.                                                                                                                                  |   | 15,396,112                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 30,917,737                                                                    |
|                                                                                                                                                             |      |   |   | Total Software & Services                                                                                                                 | $      | 30,917,737                                                                    |
|                                                                                                                                                             |      |   |   | Technology Hardware & Equipment - 5.3%                                                                                                    |   |                                                                          |
|                                                                                                                                                             |      |   |   | Communications Equipment - 3.0%                                                                                                               |   |                                                                          |
|                                                                                                                                                             | 877,868   |   |   | Cisco Systems, Inc.                                                                                                                           | $      | 25,730,311                                                                    |
|                                                                                                                                                             |      |   |   | Computer Storage & Peripherals - 1.2%                                                                                                     |   |                                                                          |
|                                                                                                                                                             | 401,146   |   |   | EMC Corp.                                                                                                                                     | $      | 10,566,186                                                                    |
|                                                                                                                                                             |      |   |   | Hardware Storage & Peripherals - 1.1%                                                                                                     |   |                                                                          |
|                                                                                                                                                             | 95,344    |   |   | Western Digital Corp.                                                                                                                         | $      | 9,282,692                                                                     |
|                                                                                                                                                             |      |   |   | Total Technology Hardware & Equipment                                                                                                     | $      | 45,579,189                                                                    |
|                                                                                                                                                             |      |   |   | Semiconductors & Semiconductor Equipment - 3.5%                                                                                           |   |                                                                          |
|                                                                                                                                                             |      |   |   | Semiconductors - 3.5%                                                                                                                         |   |                                                                          |
|                                                                                                                                                             | 92,380    |   |   | Avago Technologies, Ltd.                                                                                                                      | $      | 13,678,707                                                                    |
|                                                                                                                                                             | 295,119   |   |   | Broadcom Corp.                                                                                                                                |   | 16,777,515                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 30,456,222                                                                    |
|                                                                                                                                                             |      |   |   | Total Semiconductors & Semiconductor Equipment                                                                                            | $      | 30,456,222                                                                    |
|                                                                                                                                                             |      |   |   | Utilities - 6.7%                                                                                                                              |   |                                                                          |
|                                                                                                                                                             |      |   |   | Electric Utilities - 4.4%                                                                                                                     |   |                                                                          |
|                                                                                                                                                             | 562,742   |   |   | Exelon Corp.                                                                                                                                  | $      | 19,037,562                                                                    |
|                                                                                                                                                             | 531,155   |   |   | FirstEnergy Corp.                                                                                                                             |   | 18,951,610                                                                    |
|                                                                                                                                                             |      |   |   |                                                                                                                                          | $      | 37,989,172                                                                    |
|                                                                                                                                                             |      |   |   | Multi-Utilities - 2.3%                                                                                                                        |   |                                                                          |
|                                                                                                                                                             | 454,605   |   |   | Public Service Enterprise Group, Inc.                                                                                                         | $      | 19,379,811                                                                    |
|                                                                                                                                                             |      |   |   | Total Utilities                                                                                                                               | $      | 57,368,983                                                                    |
|                                                                                                                                                             |      |   |   | TOTAL COMMON STOCKS                                                                                                                           |   |                                                                          |
|                                                                                                                                                             |      |   |   | (Cost $786,091,877)                                                                                                                           | $      | 857,112,806                                                                   |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | TOTAL INVESTMENT IN SECURITIES - 99.6%                                                                                                        |   |                                                                          |
|                                                                                                                                                             |      |   |   | (Cost $786,091,877) (a)                                                                                                                       | $      | 857,112,806                                                                   |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | OTHER ASSETS & LIABILITIES - 0.4%                                                                                                         | $      | 3,540,301                                                                     |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | TOTAL NET ASSETS - 100.0%                                                                                                                     | $      | 860,653,107                                                                   |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             | (A.D.R.)  |   |   | American Depositary Receipt.                                                                                                                  |   |                                                                          |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             | *         |   |   | Non-income producing security.                                                                                                                |   |                                                                          |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             | (a)       |   |   | At May 31, 2015, the net unrealized appreciation on investments based on cost for federal income tax purposes of $786,091,877 was as follows: |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | Aggregate gross unrealized appreciation for all investments in which                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | there is an excess of value over tax cost                                                                                                     |   |  $          84,939,680 |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | Aggregate gross unrealized depreciation for all investments in which                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | there is an excess of tax cost over value                                                                                                     |   | (13,918,751)                                                                  |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
|                                                                                                                                                             |      |   |   | Net unrealized appreciation                                                                                                                   |   |  $          71,020,929 |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
| Various inputs are used in determining the value of the Fund’s investments.  These inputs are summarized in the three broad levels listed below. |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
| Level 1 – quoted prices in active markets for identical securities                                                                                         |      |   |
| Level 2 – other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc.)       |
| Level 3 – significant unobservable inputs (including the Fund’s own assumptions in determining fair value of investments)                            |      |   |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
| Generally, equity securities are categorized as Level 1, fixed income securities and senior loans as Level 2 and securities valued                               |      |
| using fair value methods (other than prices supplied by independent pricing services or broker-dealers) as Level 3.                                              |      |   |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |
| The following is a summary of the inputs used as of May 31, 2015, in valuing the Fund’s assets:                                                            |      |   |
|                                                                                                                                                             |      |   |   |                                                                                                                                          |   |                                                                          |

|                                                                                     |   | Level 1 |        |   | Level 2 |   |   | Level 3 |   |   | Total  |   |
|------------------------------------------------------------------------------------------|--------|---------|-------------|--------|---------|--------|--------|---------|--------|--------|--------|--------|
| Common Stocks                                                                            |   | $       | 857,112,806 |   |    | $      | -      |    |   | $      | -      |   |   | $ | 857,112,806 |   |
| Total                                                                                    |   | $       | 857,112,806 |   |    | $      | -      |    |   | $      | -      |   |   | $ | 857,112,806 |   |
|                                                                                     |   |    |        |   |    |   |   |    |   |   |   |   |   |   |   |   |
| During the period ended May 31, 2015, there were no transfers between Levels 1, 2 and 3. |   |    |        |   |    |   |   |    |   |   |   |   |   |   |   |   |