<PAGE>

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

                                   FORM 10-Q

[X]  QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES
       EXCHANGE ACT OF 1934.

               For the quarterly period ended September 30, 1999

                                      OR

[_]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
       EXCHANGE ACT OF 1934.

For the transition period from____________________to_________________________

                        Commission file number 1-13446

                         BARRETT RESOURCES CORPORATION
            (Exact name of registrant as specified in its charter)

           Delaware                                          84-0832476
  (State or other jurisdiction of                         (I.R.S. Employer)
  Incorporation or organization)                         Identification No.)

1515 Arapahoe Street, Tower 3, Suite
              1000
         Denver, Colorado                                       80202
  (Address of principal executive                             (Zip Code)
             offices)



                                (303) 572-3900
             (Registrant's telephone number, including area code)

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes [X] No [_]

     There were 32,579,326 shares of the registrant's $.01 par value common
stock outstanding as of November 9, 1999.

<PAGE>

                         BARRETT RESOURCES CORPORATION
                         -----------------------------

                                     INDEX
                                     -----

PART I.   FINANCIAL INFORMATION                                           PAGE
                                                                          ----

     Item 1.   Financial Statements

               Consolidated Condensed Balance Sheets -
               September 30, 1999 and December 31, 1998..................   3

               Consolidated Condensed Statements of
               Income - Three Months Ended
               September 30, 1999 and 1998...............................   4

               Consolidated Condensed Statements of
               Income - Nine Months Ended
               September 30, 1999 and 1998...............................   5

               Consolidated Condensed Statements of
               Cash Flows - Nine Months Ended
               September  30,  1999  and  1998...........................   6

     Item 2.   Management's Discussion and Analysis
               of Financial Condition and Results of
               Operations................................................  11

     Item 3.   Quantitative and Qualitative Disclosures
               About Market Risk ........................................  13



PART II.  OTHER INFORMATION

     Item 6.   Exhibits and Reports on Form 8-K..........................  15


<PAGE>

                         PART I. FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS
        --------------------

                         BARRETT RESOURCES CORPORATION

                     CONSOLIDATED CONDENSED BALANCE SHEETS
                                (in thousands)
<TABLE>
<CAPTION>

                                                    Sept. 30, 1999     Dec.31, 1998
                                                    --------------     ------------
                                                      (Unaudited)
<S>                                                 <C>                <C>
ASSETS
Current assets:
 Cash and cash equivalents                          $       14,604     $     14,339
 Receivables, net                                          148,220          127,798
 Inventory                                                  21,274            8,968
 Other current assets                                        5,963            2,053
                                                    --------------     ------------
    Total current assets                                   190,061          153,158

Property and equipment, net                                670,384          682,168

Other assets, net                                            3,227            3,553
                                                    --------------     ------------
                                                    $      863,672     $    838,879
                                                    ==============     ============
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
 Accounts payable                                   $      119,126     $    104,799
 Amounts payable to oil and gas property owners             24,346           16,020
 Production taxes payable                                   22,301           20,400
 Accrued and other liabilities                              10,617           17,047
                                                    --------------     ------------
    Total current liabilities                              176,390          158,266

Long-term debt                                             305,920          334,067

Deferred income taxes                                       22,678           13,294

Stockholders' equity:
 Preferred stock, $.001 par value: 1,000,000
    shares authorized, none outstanding                         --               --
 Common stock, $.01 par value: 45,000,000
    shares authorized; 32,602,013 issued
    (32,002,304 at December 31, 1998)                          326              320
 Additional paid-in capital                                271,902          261,998
 Retained earnings                                          87,082           70,934
 Treasury stock, at cost                                      (626)              --
                                                    --------------     ------------
    Total stockholders' equity                             358,684          333,252
                                                    --------------     ------------
                                                    $      863,672     $    838,879
                                                    ==============     ============
</TABLE>

                            See accompanying notes.

                                       3
<PAGE>

                         BARRETT RESOURCES CORPORATION

                  CONSOLIDATED CONDENSED STATEMENTS OF INCOME

                                  (UNAUDITED)
                     (in thousands, except per share data)
<TABLE>
<CAPTION>

                                                                  Three Months Ended
                                                      -----------------------------------------
                                                        Sept. 30, 1999          Sept. 30, 1998
                                                      ------------------      -----------------
<S>                                                   <C>                     <C>
Revenues:
 Oil and gas production                               $           57,670      $          47,745
 Trading revenues                                                219,869                 98,582
 Interest income                                                     151                    156
 Other income                                                      1,236                    258
                                                      ------------------      -----------------
                                                                 278,926                146,741

Operating expenses:
 Lease operating expenses                                         16,517                 13,219
 Cost of trading                                                 220,091                 94,460
 Depreciation, depletion and amortization                         24,106                 25,502
 General and administrative                                        5,816                  5,066
 Interest expense                                                  5,419                  5,255
 Other                                                                 1                    252
                                                      ------------------      -----------------
                                                                 271,950                143,754
                                                      ------------------      -----------------

Income for the period before income taxes                          6,976                  2,987

Provision for income taxes                                         2,652                  1,135
                                                      ------------------      -----------------
Net income for the period                             $            4,324      $           1,852
                                                      ==================      =================

Earnings per common share

 Basic                                                $             0.13      $            0.06
                                                      ==================      =================
 Assuming dilution                                    $             0.13      $            0.06
                                                      ==================      =================
</TABLE>

                            See accompanying notes.

                                       4
<PAGE>

                         BARRETT RESOURCES CORPORATION

                  CONSOLIDATED CONDENSED STATEMENTS OF INCOME

                                  (UNAUDITED)
                     (in thousands, except per share data)
<TABLE>
<CAPTION>

                                                                      Nine Months Ended
                                                        -----------------------------------------
                                                          Sept. 30, 1999          Sept. 30, 1998
                                                        ------------------      -----------------
<S>                                                     <C>                     <C>
Revenues:
 Oil and gas production                                 $          153,718      $         154,877
 Trading revenues                                                  568,337                249,700
 Interest income                                                       609                    511
 Other income                                                        3,723                  5,304
                                                        ------------------      -----------------
                                                                   726,387                410,392

Operating expenses:
 Lease operating expenses                                           44,168                 41,756
 Cost of trading                                                   550,489                240,236
 Depreciation, depletion and amortization                           71,572                 74,738
 General and administrative                                         17,936                 19,354
 Interest expense                                                   16,000                 14,672
 Other                                                                 158                  2,412
                                                        ------------------      -----------------
                                                                   700,323                393,168
                                                        ------------------      -----------------

Income for the period before income taxes                           26,064                 17,224

Provision for income taxes                                           9,916                  6,545
                                                        ------------------      -----------------

Net income for the period                               $           16,148      $          10,679
                                                        ==================      =================

Earnings per common share

 Basic                                                  $             0.50      $            0.34
                                                        ==================      =================
 Assuming dilution                                      $             0.49      $            0.33
                                                        ==================      =================
</TABLE>

                            See accompanying notes.

                                       5
<PAGE>

                         BARRETT RESOURCES CORPORATION
                CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS
                                  (UNAUDITED)
                                (in thousands)
<TABLE>
<CAPTION>

                                                                                        Nine Months Ended
                                                                           ----------------------------------------
                                                                             Sept. 30, 1999         Sept. 30, 1998
                                                                           -------------------   ------------------
<S>                                                                        <C>                   <C>
Cash flows from operations:
 Net income                                                                $            16,148   $           10,679
 Adjustments needed to reconcile to net cash
   provided by operations:
     Depreciation, depletion and amortization                                           71,898               75,061
     Deferred income taxes                                                               9,384                6,284
     Other                                                                                (576)              (1,392)
                                                                           -------------------   ------------------
                                                                                        96,854               90,632
     Change in current assets and liabilities:
       Accounts receivable                                                             (20,422)              13,895
       Other current assets                                                            (16,031)             (11,646)
       Accounts payable                                                                 14,327               14,878
       Amounts due oil and gas owners                                                    8,326              (11,442)
       Production taxes payable                                                          1,901                3,519
       Accrued and other liabilities                                                    (4,966)              (8,661)
                                                                           -------------------   ------------------
Net cash flow provided by operations                                                    79,989               91,175
                                                                           -------------------   ------------------

Cash flows from investing activities:
 Proceeds from sale of oil and gas properties                                           12,550                4,021
 Acquisition of property and equipment                                                 (72,523)            (156,333)
                                                                           -------------------   ------------------
Net cash flow used in investing activities                                             (59,973)            (152,312)
                                                                           -------------------   ------------------

Cash flows from financing activities:
   Borrowings under line of credit                                                      35,000               91,000
   Proceeds from issuance of common stock                                                9,285                3,999
   Payments under line of credit                                                       (60,000)             (36,000)
   Payments on other long-term debt                                                     (4,035)                (612)
   Treasury stock purchased                                                                 (1)                  --
   Other                                                                                    --                 (151)
                                                                           -------------------   ------------------

Net cash flow provided by (used in) financing activities                               (19,751)              58,236
                                                                           -------------------   ------------------

Increase (decrease) in cash and cash equivalents                                           265               (2,901)
Cash and cash equivalents at beginning of period                                        14,339               14,479
                                                                           -------------------   ------------------

Cash and cash equivalents at end of period                                 $            14,604   $           11,578
                                                                           ===================   ==================

Non-cash investing and financing activities:
   Issuance of common stock for property acquisition                                        --   $            9,116
   Common Stock/treasury share options exercised                           $               627   $               60
</TABLE>

                            See accompanying notes.

                                       6
<PAGE>

                         BARRETT RESOURCES CORPORATION
             NOTES TO CONSOLIDATED CONDENSED FINANCIAL STATEMENTS
                              September 30, 1999

1.   UNAUDITED CONSOLIDATED CONDENSED FINANCIAL STATEMENTS

     In the opinion of management, the accompanying unaudited consolidated
     condensed financial statements contain all adjustments necessary to present
     fairly the financial position of Barrett Resources Corporation and its
     subsidiaries, collectively referred to as the "Company", as of September
     30, 1999 and the results of operations and cash flows for the periods
     presented. All of the Company's subsidiaries are wholly owned. All such
     adjustments are of a normal recurring nature. The results of operations for
     the periods presented are not necessarily indicative of the results for the
     full year.

     The accounting policies followed by the Company are set forth in Note 1 to
     the Company's financial statements in Form 10-K for the year ended December
     31, 1998. These financial statements should be read in conjunction with the
     financial statements and notes included in the Form 10-K.

2.   INCOME TAXES

     Provisions for income taxes were calculated in accordance with Statement of
     Financial Accounting Standards No. 109 which provides that a deferred tax
     liability or asset be determined based on the timing differences between
     the basis used for financial versus tax reporting of assets and liabilities
     as measured by the effective tax rates. For the quarter ended September 30,
     1999, the Company used an estimated effective tax rate of 38 percent.

     In July 1999, Plains Petroleum Company ("Plains"), a wholly owned
     subsidiary of the Company, received a favorable ruling from the United
     States Tax Court in a case stemming from an Internal Revenue Service
     ("IRS") examination of Plains' federal tax returns filed for the years 1991
     through 1993. As a result of its examination, the IRS in 1996 had issued a
     "Notice of Deficiency" of $5.3 million with penalties and an undetermined
     amount of interest. The deficiency resulted primarily from the IRS's
     disallowance of certain net operating loss deductions claimed during the
     periods under examination. The IRS has until January 25, 2000 to appeal the
     ruling from the United States Tax Court.

     The IRS has also examined the federal tax returns of the Company for the
     periods ended July 1995, December 1995 and December 1996. The IRS issued a
     letter proposing changes to tax for those periods totaling $5.7 million.
     The proposed tax changes resulted primarily from the disallowance of net
     operating loss and merger related deductions claimed for the periods ended
     December 1995 and 1996. The net operating losses relate to the same net
     operating loss carry forwards involved in the Plains tax returns for years
     1991 through 1993.

3.   LONG-TERM DEBT

     The Company's long-term debt consists of the following (in thousands):

                                       7
<PAGE>



                                        September 30,            December 31,
                                             1999                   1998
                                        -------------            -------------
Line of Credit                          $     150,000            $     175,000
7.55% Senior Notes                            150,000                  150,000
Production Payments                            10,364                   14,399
                                        -------------            -------------
    Total                                     310,364                  339,399
Less:  current portion                          4,444                    5,332
                                        -------------            -------------
Long-term debt                          $     305,920            $     334,067
                                        =============            =============

     As of September 30, 1999 the Company's effective interest rate, on an
     outstanding balance of $150 million on its line of credit, was 5.71% per
     annum.

     Total interest expense paid for the nine months ended September 30, 1999
     was $18.8 million compared to $16.8 million for the nine months ended
     September 30, 1998.

4.   EARNINGS PER SHARE

     The following data show the amounts used in computing earnings per share
     and the effect on income and the weighted average number of shares of
     dilutive potential common stock.

<TABLE>
<CAPTION>
                                                                                        Three Months Ended
                                                                                      Sept. 30,     Sept. 30,
              (in thousands)                                                            1999          1998
                                                                                     -----------   -----------
<S>                                                                                  <C>           <C>
Income available to common stockholders                                              $     4,324   $     1,852
                                                                                     ===========   ===========
Weighted average number of common shares used in
  basic EPS                                                                               32,431        31,890

Effect of dilutive securities:
  Stock options                                                                              778           234
  Written put option                                                                          56           150
                                                                                     -----------   -----------

Weighted number of common shares and dilutive
   potential common stock used in EPS -
   assuming dilution                                                                      33,265        32,274
                                                                                     ===========   ===========

                                                                                          Nine Months Ended
                                                                                        Sept. 30,   Sept. 30,
(in thousands)                                                                            1999        1998
                                                                                     -----------   -----------
Income available to common stockholders                                              $    16,148   $    10,679
                                                                                     ===========   ===========
Weighted average number of common shares used in
  basic EPS                                                                               32,212        31,693

Effect of dilutive securities:
  Stock options                                                                              357           353
  Written put option                                                                         118           150
                                                                                     -----------   -----------

Weighted number of common shares and dilutive
  potential common stock used in EPS -
  assuming dilution                                                                       32,687       32,196
                                                                                     ===========   ===========
</TABLE>

                                       8
<PAGE>

     On August 3, 1999, the holder of the written put option elected to exercise
     such option and, accordingly, the Company issued 150,000 shares of its
     common stock. In conjunction with the exercise of this option, the Company
     received the holders' one percent interest in a subsidiary of the Company.
     In addition, with the exercise of the put option, the Company's written
     call option, as described in the financial statements and notes of the
     Company's Form 10-K, was terminated.

5.   RECENTLY ISSUED ACCOUNTING STANDARDS

     In June 1999, the Financial Accounting Standards Board issued Statement of
     Financial Accounting Standards No. 137 ("SFAS 137"), "Accounting for
     Derivative Instruments and Hedging Activities - Deferral of the Effective
     Date of FASB Statement No. 133". FASB Statement No. 133 ("SFAS 133")
     establishes accounting and reporting standards requiring that every
     derivative instrument (including certain derivative instruments embedded in
     other contracts) be recorded in the balance sheet as either an asset or
     liability measured at its fair value. It also requires that changes in the
     derivative's fair value be recognized currently in earnings unless specific
     hedge accounting criteria are met. Special accounting for qualifying hedges
     allows a derivative's gains and losses to offset related results on the
     hedged item in the income statement, and requires that a company must
     formally document, designate, and assess the effectiveness of transactions
     that receive hedge accounting. FASB Statement No. 133 is effective for
     fiscal years beginning after June 15, 2000, as amended in SFAS 137, and
     cannot be applied retroactively. The Company has not yet quantified the
     impacts of adopting SFAS 133 on its financial statements and has not
     determined the timing of or method of adoption of SFAS 133. However, SFAS
     133 could increase volatility in earnings and other comprehensive income.

6.   BUSINESS SEGMENT INFORMATION

     The Company operates principally in two business segments: natural gas
     trading and oil and gas exploration, development and production. In
     addition to marketing its own gas, the Company engages in natural gas
     trading activities, which involves purchasing natural gas from third
     parties and selling natural gas to other parties at prices and volumes that
     management anticipates will result in profits to the Company.

     The Company evaluates segment performance based on the profit or loss from
     operations before income taxes. Corporate general and administrative
     expenses are unallocated except for certain direct costs associated with
     the Company's trading activity. Consolidated and segment financial
     information is as follows:

<TABLE>
<CAPTION>

Quarter ended Sept. 30, 1999    Natural
---------------------------       Gas         Oil & Gas      Segment       Corporation
       (in thousands)           Trading          E&P          Total       & Unallocated     Consolidated
      ---------------
--------------------------------------------------------------------------------------------------------
<S>                           <C>             <C>           <C>           <C>               <C>
Revenues                        $219,869        $57,742      $277,611      $  1,164             $278,775
Interest Income                        0              0             0           151                  151
                              --------------------------------------------------------------------------
  Total Revenues                 219,869         57,742       277,611         1,315              278,926
DD&A                                   0         22,997        22,997         1,109               24,106
Profit (loss)                       (222)        18,228        18,006       (11,030)               6,976
Expenditures for assets                0         19,465        19,465           774               20,239

</TABLE>

                                       9
<PAGE>
<TABLE>
<CAPTION>


Quarter ended Sept. 30, 1998    Natural
----------------------------      Gas       Oil & Gas      Segment      Corporation
     (in thousands)             Trading        E&P          Total      & Unallocated    Consolidated
    ---------------
----------------------------------------------------------------------------------------------------
<S>                           <C>         <C>            <C>         <C>              <C>
Revenues                       $ 98,582    $ 46,800       $145,382         $1,203           $146,585

Interest Income                       0           0              0            156                156
                              ----------------------------------------------------------------------
  Total Revenues                 98,582      46,800        145,382          1,359            146,741

DD&A                                  0      24,444         24,444          1,058             25,502

Profit (loss)                     4,122       9,136         13,258        (10,271)             2,987

Expenditures for assets               0      56,366         56,366            378             56,744

Nine Months ended               Natural
-----------------                 Gas       Oil & Gas      Segment      Corporation
 Sept. 30, 1999                 Trading        E&P          Total      & Unallocated    Consolidated
 --------------
 (in thousands)
 --------------
----------------------------------------------------------------------------------------------------
<S>                           <C>         <C>            <C>         <C>              <C>
Revenues                       $568,337    $153,876       $722,213         $3,565           $725,778

Interest Income                       0           0              0            609                609
                              ----------------------------------------------------------------------
  Total Revenues                568,337     153,876        722,213          4,174            726,387

DD&A                                  0      68,282         68,282          3,290             71,572

Profit (loss)                    17,848      41,426         59,274        (33,210)            26,064

Expenditures for assets               0      58,499         58,499          1,474             59,973

Nine Months ended               Natural
-----------------                 Gas       Oil & Gas      Segment      Corporation
 Sept. 30, 1998                 Trading        E&P          Total      & Unallocated    Consolidated
 --------------
 (in thousands)
 --------------
----------------------------------------------------------------------------------------------------
<S>                           <C>         <C>            <C>         <C>              <C>
Revenues                       $249,700    $156,006       $405,706         $4,175           $409,881

Interest Income                       0           0              0            511                511
                              ----------------------------------------------------------------------
  Total Revenues                249,700     156,006        405,706          4,686            410,392

DD&A                                  0      71,619         71,619          3,119             74,738

Profit (loss)                     9,464      42,631         52,095        (34,871)            17,224

Expenditures for assets               0     158,926        158,926          2,501            161,427
</TABLE>

                                       10
<PAGE>

                         BARRETT RESOURCES CORPORATION
                  For the Quarter Ended and Nine Months Ended
                              September 30, 1999

Item 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
         ---------------------------------------------------------------
         RESULTS OF OPERATIONS
         ---------------------

Liquidity and Capital Resources
-------------------------------

     For the nine months ended September 30, 1999, total assets increased $24.8
     million, or 3 percent, to $863.7 million as compared with total assets of
     $838.9 million at December 31, 1998. Cash and cash equivalents increased
     $0.3 million to $14.6 million, working capital increased $18.8 million to
     $13.7 million, and net property and equipment decreased $11.8 million to
     $670.4 million.

     Operating cash flows before working capital adjustments totaled $30.9
     million in the third quarter of 1999 compared with $28.2 million in the
     third quarter of 1998. After working capital adjustments, cash flow
     provided by operations decreased by $11.4 million to $9.7 million as
     compared with the same period in 1998.

     Capital expenditures of $29.1 million for the quarter represent a decrease
     of $19.1 million from the same period in 1998. These expenditures, funded
     by operating cash flows, consisted principally of drilling and development
     activities and acquisitions of oil and gas properties. Of these capital
     expenditures, approximately 89 percent was invested in the Rocky Mountain
     Region, principally in the Piceance, Powder River and Wind River Basins,
     and 6 percent in the Mid-Continent Region. The Company recently increased
     the 1999 capital expenditures budget from $111 million to $130 million. The
     1998 capital expenditures budget was $206 million. In an effort to maintain
     debt levels, management continues to be sensitive to fluctuations in
     product prices and will reassess the capital expenditure levels relative to
     such fluctuations and the Company's cash flows.

     On October 29, 1999, the Company sold certain gas properties principally
     located in the Texas and Oklahoma panhandles, effective September 1, 1999,
     for $8.2 million. These properties represented less than two percent of the
     Company's proved reserves and production. On November 1, 1999, the Company
     sold its interests in certain non-producing oil and gas leases in the Gulf
     of Mexico for $7.0 million.

     The Company plans to continue actively acquiring, exploring and developing
     oil and gas properties. The Company expects cash flow from its producing
     properties and its borrowing capacity to be sufficient to fund its
     anticipated capital and operating requirements, including any
     contingencies.

     Information regarding the Company's Year 2000 readiness is contained in the
     Company's annual report on Form 10-K for the year ended December 31, 1998
     and reference is made to the information contained there. There has been no
     material change in the status of the Company's Year 2000 readiness program.
     As of July 1999, the Company verified that all IT hardware systems,
     including network and embedded systems, are Year 2000 compliant. All
     software systems utilized by the Company are Year 2000 compliant with the
     exception of one program used to access an outside database. The vendor
     providing this program is continuing to perform Beta tests on its updated
     software. The Company's costs associated with completing its Year 2000-
     readiness program are not expected to exceed $250,000. Costs incurred to
     date are nominal and are included in normal operating expense.


                                       11
<PAGE>

     The Company's operating results are directly affected by oil and gas
     prices. Oil and gas prices also affect the reserve values used in
     determining the "ceiling test" limitation for the Company's capitalized oil
     and gas property costs accounted for under the full cost method. Should the
     net capitalized costs of the Company's oil and gas properties exceed the
     estimated present value of future net cash flows from proved oil and gas
     reserves, such excess costs would be recognized as an impairment and
     charged to current expense. A decline in oil and gas sales prices could
     possibly result in the recognition of an impairment expense in future
     periods.

Results of Operations
---------------------

     Net income for the quarters ended September 30, 1999 and 1998 was $4.3
     million ($.13 per share, assuming dilution) and $1.9 million ($.06 per
     share, assuming dilution), respectively. This increase is primarily due to
     higher average prices for oil and gas.

     Total revenues for the quarter were $278.9 million, up 90 percent compared
     to $146.7 million for the same period in 1998. This increase is principally
     attributed to a $121.3 million increase in trading revenues.

     Production revenue for the third quarter of 1999 increased from $47.7
     million to $57.7 million. Production revenues and related volumes and
     average prices during the periods presented were as follows:


<TABLE>
<CAPTION>





                             Quarter Ended      Nine Months Ended
                             September 30,        September 30,
                            ----------------   ------------------
                              1999     1998      1999      1998
                              ----     ----      ----      ----
<S>                         <C>      <C>       <C>       <C>
Gas Revenues (000's)        $52,293  $42,538   $139,742  $135,691
Gas Production (Bcf)           24.3     23.0       71.2      70.5
Average Price per Mcf       $  2.15  $  1.85   $   1.96  $   1.92

Oil Revenues (000's)        $ 5,377  $ 5,207   $ 13,976  $ 19,186
Oil Production (MBbls)          358      492      1,125     1,619
Average Price per Barrel    $ 15.02  $ 10.58   $  12.42  $  11.85
</TABLE>

     (Note: Bcf = billion cubic feet; Mcf = thousand cubic feet; MBbls =
     thousand barrels.)

     Third quarter gas revenues increased 23 percent as compared with the same
     period in 1998, principally due to a 16 percent increase in average prices
     and a 6 percent increase in production volumes.

     The 3 percent increase in third quarter 1999 oil revenues from the same
     period in 1998 is attributed to a 42 percent increase in average oil prices
     partially offset by a 27 percent decrease in production volumes. The
     decline in oil production is primarily due to the selling of various Gulf
     of Mexico wells and lower capital spending on oil projects in the first
     nine months of 1999.

     For the quarter ended September 30, 1999, revenues from trading were $219.9
     million compared to $98.6 million for the same period in 1998. The
     associated costs of trading increased to $220.1 million from $94.5 million.
     Gross profit from trading was a negative $0.2 million for the quarter ended
     September 30, 1999 compared to $4.1 million for the quarter ended September
     30, 1998.

     To reduce its exposure to volatile oil and gas price fluctuations, the
     Company enters into hedging arrangements for both trading and producing
     activities. During the third quarter ended September 30, 1999, the

                                       12
<PAGE>

     Company recognized net production hedging losses of approximately $1.5
     million for oil and $4.6 million for gas. These hedging losses were
     recorded in the consolidated statements of income as adjustments to oil and
     gas production revenue. The Company realized net hedging income on its
     trading activities of approximately $2.3 million during the third quarter.

     Depreciation, depletion and amortization decreased in 1999 to $24.1 million
     from $25.5 million in 1998 due to a decrease in the depletion rate from
     $.94 to $.87 per Mcfe.

     Interest expense for the third quarter increased from $5.3 million in 1998
     to $5.4 million in 1999.

     The Company's largest sources of operating income are from trading
     activities and oil and gas production. The levels of the Company's revenues
     and earnings from gas and oil production and trading activities are
     affected by prices at which natural gas and oil are being sold. This is
     particularly true with respect to natural gas, which accounted for
     approximately 91 percent of the Company's production revenue and all of its
     trading activities for the third quarter of 1999. As a result, the
     Company's operating results for any prior period are not necessarily
     indicative of future operating results because of the fluctuations in gas
     and oil prices and the lack of predictability of those fluctuations as well
     as changes in production levels.

Item 3.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
         ----------------------------------------------------------

  Commodity Price Risk
  --------------------

     The Company uses commodity derivative financial instruments, including
     futures and swaps, to reduce the effect of natural gas price volatility on
     a portion of its natural gas and crude oil production. Natural gas
     commodity swap agreements are generally used to fix a price at the natural
     gas market location or to fix a price differential between the price of
     natural gas at Henry Hub and the price of gas at its market location.
     Settlements are based on the difference between a fixed and a variable
     price as specified in the agreement. The following table summarizes the
     Company's derivative financial instrument position on its natural gas and
     crude oil production as of September 30, 1999. The fair value of these
     instruments reflects the estimated amounts that the Company would receive
     or pay to settle the contracts as of September 30, 1999. Actual settlement
     of these instruments as they mature will differ from these estimates. Gains
     or losses realized from these instruments hedging the Company's production
     are expected to be offset by corresponding changes in the sales value of
     the Company's natural gas and crude oil production.


         Natural Gas
     ----------------------------------------------------------------------
        For the period  |    MMBtu     |Price Range Per |   Fair Value
                        |              |     MMBtu      |
     ----------------------------------------------------------------------
        9/1999 - 2/2003 | 77.1 million | $1.72 - $2.03  | $(42.9) million
     ----------------------------------------------------------------------

         Crude Oil
     ----------------------------------------------------------------------
        For the period  |   Barrels    |Price Range Per |   Fair Value
                        |              |     Barrel     |
     ----------------------------------------------------------------------
       9/1999 - 12/1999 | 0.6 million  |     $15.00     |  $(2.1) million
     ----------------------------------------------------------------------

     The Company also uses commodity derivative financial instruments in its
     trading activities to hedge price fluctuations, to hedge the value of
     stored gas and to lock in margins on its trading positions. The following
     table summarizes the Company's derivative financial instrument position on
     its natural gas and crude oil trading activities as of September 30, 1999.
     The fair value of these instruments reflects the estimated amounts that the
     Company would receive or pay to settle the

                                       13
<PAGE>

     contracts as of September 30, 1999. Actual settlement of these instruments
     as they mature will differ from these estimates. Gains or losses realized
     from these instruments hedging the Company's trading activities are
     expected to be offset by corresponding changes in the settlement value of
     actual natural gas and crude oil traded.

      Natural Gas
    -------------------------------------------------------------------
     For the period  |   MMBtU      |  Price Range Per |  Fair Value
                     |              |      MMBtu       |
    -------------------------------------------------------------------
    9/1999 - 12/2004 | 578 million  |   $1.53 - $3.22  | $24.1 million
    -------------------------------------------------------------------

        Crude Oil
    -------------------------------------------------------------------
      For the period |   Barrels    |  Price Range Per |  Fair Value
                     |              |      Barrel      |
    -------------------------------------------------------------------
    9/1999 - 10/2000 | 2.7 million  |   $13.98 - $22.20| $ 0.4 million
    -------------------------------------------------------------------

Interest Rate Risk
------------------

     The Company's use of fixed and variable rate long-term debt to partially
     finance capital expenditures exposes the Company to market risk related
     changes in interest rates. As of September 30, 1999, there have been no
     material changes in the Company's interest rate risk exposure, from that
     disclosed in the 1998 Form 10-K.

     _______________________________________________________________________

     This report contains forward-looking statements within the meaning of
     Section 27A of the Securities Act of 1933 and Section 21E of the Securities
     Exchange Act of 1934. Although the Company believes that the expectations
     reflected in the forward-looking statements and the assumptions upon which
     such forward-looking statements are based are reasonable, it can give no
     assurance that such expectations and assumptions will prove to have been
     correct. See the Company's Annual Report on Form 10-K for additional
     statements concerning important factors that could cause actual results to
     differ materially from the Company's expectations.

                                       14
<PAGE>

                          PART II. OTHER INFORMATION

Item 6.   Exhibits and Reports on Form 8-K
          --------------------------------

          (a)   The following Exhibit is filed as part of this Quarterly Report
                on Form 10-Q:

                27.1 Financial Data Schedule

          (b)   During the quarter ended September 30, 1999, the Registrant
                filed one report on Form 8-K reporting an event occurring on
                August 20, 1999.

                                       15
<PAGE>

                                  SIGNATURES
                                 ------------

     Pursuant to the requirements of the Securities and Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                       BARRETT RESOURCES CORPORATION

November 12, 1999                      By /s/ A. Ralph Reed
                                          ---------------------------------
                                          A. Ralph Reed
                                          President and Chief Operating Officer


November 12, 1999                      By /s/ J. Frank Keller
                                          ---------------------------------
                                          J. Frank Keller
                                          Chief Financial Officer




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