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 March 31, 2010 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        333-104061-01

BCTC IV ASSIGNOR CORP.(Exact name of registrant as specified in its charter)



|Delaware                          | 04-3208532         
|--------------------------------- | -------------------
|(State or other jurisdiction      | (I.R.S. Employer   
|of incorporation or organization) | Identification No.)

One Boston Place, Suite 2100, Boston, Massachusetts  02108

Registrant's telephone number, including area code (617)624-8900





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.

|Yesý | No 
|---- | ----

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).

|Yes  | No 
|----- | ----

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definition of "large accelerated filer," "accelerated filer," and "smaller reporting company" in Rule 12b-2 of the Exchange Act (check one):

|Large accelerated filer  | Accelerated filer        
|------------------------- | --------------------------
|Non-accelerated filer    | Smaller reporting companyý



Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

|Yesý | No 
|---- | ----









DOCUMENTS INCORPORATED BY REFERENCE

The following documents of the Corporation are incorporated by reference:





|Form 10-Q   |                                                                             
|----------- | ----------------------------------------------------------------------------
|Parts       | Document                                                                    
|            |                                                                             
|Parts I, II | Form 10-K of BCTC IV Assignor Corp. dated December 31, 2009, as supplemented
|            |                                                                             
|            |                                                                             











BCTC IV ASSIGNOR CORP.

Form 10-Q QUARTERLY REPORT FOR THE PERIOD ENDED MARCH 31, 2010

TABLE OF CONTENTS





|         | PART I - FINANCIAL INFORMATION                             
|-------- | -----------------------------------------------------------
|         |                                                            
|Item 1.  | Financial Statements                                       
|         |                                                            
|Item 2.  | Management's Discussion and Analysis of Financial          
|         | Condition and Results of Operations                        
|         |                                                            
|Item 3.  | Quantitative and Qualitative Disclosures about Market Risk 
|         |                                                            
|Item 4.  | Controls and Procedures                                    
|         |                                                            
|         | PART II - OTHER INFORMATION                                
|         |                                                            
|Item 1.  | Legal Proceedings                                          
|         |                                                            
|Item 1A. | Risk Factors                                               
|         |                                                            
|Item 2.  | Unregistered Sales of Equity Securities and Use of Proceeds
|         |                                                            
|Item 3.  | Defaults Upon Senior Securities                            
|         |                                                            
|Item 4.  | (Removed and Reserved.)                                    
|         |                                                            
|Item 5.  | Other Information                                          
|         |                                                            
|Item 6.  | Exhibits                                                   
|         |                                                            
|         | Signatures                                                 

























PART I



BCTC IV Assignor Corp.

Balance Sheets





|                                     | March 31,
2010(Unaudited)                                                                       | December 31,
2009(Audited)
|------------------------------------ | ----------------------------------------------------------------------------------------------- | --------------------------
|                                     |                                                                                                 |                           
|ASSETS                              
|                                     |                                                                                                 |                           
|INVESTMENTS IN OPERATING             |                                                                                                 |                           
|                                     | PARTNERSHIPS (Note B)                                                                           | $  100                    
|                                     |                                                                                                 |                           
|                                     | $100                                                                                            | $100                      
|                                     |                                                                                                 |                           
|                                    
|LIABILITIES AND STOCKHOLDER'S EQUITY
|                                     |                                                                                                 |                           
|LIABILITIES                          |                                                                                                 |                           
|                                     |                                                                                                 |                           
|Subscription payable                 | $100                                                                                            | $100                      
|                                     |                                                                                                 |                           
|                                     | 100                                                                                             | 100                       
|                                     |                                                                                                 |                           
|Stockholder's equity                 |                                                                                                 |                           
|                                     | Common stock - 1,000 shares authorized, issued and outstanding, $1 par value per share (Note A) | 1,000                     
|Less: subscription receivable        | (1,000)                                                                                         | (1,000)                   
|                                     |                                                                                                 |                           
|                                     | $100                                                                                            | $100                      
|                                     |                                                                                                 |                           

NOTE A - ORGANIZATION

BCTC IV Assignor Corp. (the "Corporation") was organized on October 12, 1993 under the laws of the State of Delaware to act as the assignor limited partner of, and to acquire and hold a limited partnership interest in, Boston Capital Tax Credit Fund IV L.P. (the "Limited Partnership"). The Corporation will assign units of beneficial interest in its limited partnership interest to persons who purchase Beneficial Assignee Certificates (BACs), on the basis of one unit of beneficial interest for each BAC. The Corporation will not have any interest in profits, losses or distributions on its own behalf.

NOTE B - INVESTMENT IN LIMITED PARTNERSHIP

On October 12, 1993, the Corporation was admitted as the assignor limited partner in the Limited Partnership. The Limited Partnership was formed to invest in real estate by acquiring, holding, and disposing of limited partnership interests in operating partnerships which will acquire, develop, rehabilitate, operate and own newly-constructed, existing or rehabilitated low-income apartment complexes.

NOTE C - RECENT ACCOUNTING PRONOUNCEMENTS

In May 2009, the FASB issued guidance regarding subsequent events, which was subsequently updated in February 2010. This guidance established general standards of accounting for and disclosure of events that occur after the balance sheet date but before financial statements are issued or are available to be issued. In particular, this guidance sets forth the period after the balance sheet date during which management of a reporting entity should evaluate events or transactions that may occur for potential recognition or disclosure in the financial statements, the circumstances under which an entity should recognize events or transactions occurring after the balance sheet date in its financial statements, and the disclosures that an entity should make about events or transactions that occurred after the balance sheet date. This guidance was effective for financial statements issued for fiscal years and interim periods ending after June 15, 2009, and was therefore adopted by the Company for the quarter ended June 30, 2009. The adoption did not have a significant impact on the subsequent events that the Corporation reports, either through recognition or disclosure, in the financial statements. In February 2010, the FASB amended its guidance on subsequent events to remove the requirement to disclose the date through which an entity has evaluated subsequent events, alleviating conflicts with current SEC guidance. This amendment was effective immediately and therefore the Corporation did not include the disclosure in this Form 10-Q.

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

Business

The Corporation was formed for the sole purpose of serving as an assignor for the Limited Partnership and will not engage in any other business. Units of beneficial interest in the Limited Partnership interest of the Corporation will be assigned by the Corporation by means of BACs to investors and investors will be entitled to all the rights and economic benefits of a limited partner of the Limited Partnership, including rights to a percentage of the income, gains, losses, deductions, credits and distributions of the Limited Partnership. The Corporation is wholly-owned by John P. Manning.
A Registration Statement on Form S-11 and the related prospectus, as supplemented (the "Prospectus") were filed with the Securities and Exchange Commission and became effective December 16, 1993 in connection with a public offering ("Offering") in one or more series of a minimum of 250,000 BACs and a maximum of 30,000,000 BACs at $10 per BAC. On April 18, 1996 an amendment to Form S-11, which registered an additional 10,000,000 BACs for sale to the public in one or more series, became effective. On April 2, 1998 an amendment to Form S-11, which registered an additional 25,000,000 BACs for sale to the public in one or more series, became effective. On August 31, 1999 an amendment to Form S-11, which registered an additional 8,000,000 BACs for sale to the public became effective. On July 26, 2000 an amendment to Form S-11, which registered an additional 7,500,000 BACs for sale to the public became effective. On July 23, 2001 an amendment to Form S-11, which registered an additional 7,000,000 BACs for sale to the public became effective. On July 24, 2002 an amendment to Form S- 11, which registered an additional 7,000,000 BACs for sale to the public became effective. On July 2, 2003, an amendment to Form S-11, which registered an additional 7,000,000 BACs for sale to the public became effective. As of March 31, 2010, subscriptions had been received and accepted by the general partner of the Limited Partnership in Series 20, Series 21, Series 22, Series 23, Series 24, Series 25, Series 26, Series 27, Series 28, Series 29, Series 30, Series 31, Series 32, Series 33, Series 34, Series 35, Series 36, Series 37, Series 38, Series 39, Series 40, Series 41, Series 42, Series 43, Series 44, Series 45 and Series 46 for 83,651,080 BACs representing capital contributions of $836,177,880.

The Offering, including information regarding the issuance of BACs in series, is described on pages 144 to 149 of the Prospectus, as supplemented, under the caption "The Offering", which is incorporated herein by reference.

Description of Business

The Corporation's sole purpose is to act as a conduit through which all of the economic and tax benefits of an investment in the Limited Partnership are passed along to the investor holders. The Corporation does not charge any fees for its services and has no income.
The Limited Partnership's principal business is to invest as a limited partner in other limited partnerships (the "Operating Partnerships"), each of which will own or lease and will operate an apartment complex exclusively or partially for low- and moderate-income tenants. Each Operating Partnership in which the Limited Partnership invests will own apartment complexes which are completed, newly-constructed, under construction or rehabilitation, or to-be constructed or rehabilitated, and which are expected to receive government assistance. Each apartment complex is expected to qualify for the low-income housing tax credit under Section 42 of the Internal Revenue Code of 1986, as amended (the "Code")(the "Federal Housing Tax Credit"), and provide tax benefits over a period of ten to twelve years in the form of tax credits which investors may use to offset income, subject to strict limitations, from other sources. Some apartment complexes may also qualify for the historic rehabilitation tax credit under Section 47 of the Code (the "Rehabilitation Tax Credit"). The Federal Housing Tax Credit and the government assistance programs are described on pages 64 to 88 of the Prospectus, as supplemented, under the captions "Tax Credit Programs" and "Government Assistance Programs," which are incorporated herein by reference. Section 236 (f) (ii) of the National Housing Act, as amended, and Section 101 of the Housing and Urban Development Act of 1965, as amended, each provide for the making by HUD of rent supplement payments to low income tenants in properties which receive other forms of federal assistance such as tax credits. The payments for each tenant, which are made directly to the owner of their property, generally are in amounts as to enable the tenant to pay rent equal to 30% of the adjusted family income. Some of the apartment complexes in which the Limited Partnership has invested are receiving rent supplements from HUD. HUD has been in the process of converting rent supplement assistance to assistance paid not to the owner of the apartment complex, but directly to the individuals. At this time, the Limited Partnership is unable to predict whether Congress will continue rent supplement programs payable directly to owners of the apartment complex.



As of March 31, 2010, the Limited Partnership had invested in 21 Operating Partnerships on behalf of Series 20, 10 Operating Partnership on behalf of Series 21, 25 Operating Partnerships on behalf of Series 22, 20 Operating Partnerships on behalf of Series 23, 20 Operating Partnerships on behalf of Series 24, 20 Operating Partnerships on behalf of Series 25, 43 Operating Partnerships on behalf of Series 26, 16 Operating Partnerships on behalf of Series 27, 26 Operating Partnerships on behalf of Series 28, 21 Operating Partnerships on behalf of Series 29, 18 Operating Partnerships on behalf of Series 30, 26 Operating Partnerships on behalf of Series 31, 16 Operating Partnerships on behalf of Series 32, 10 Operating Partnerships on behalf of Series 33, 14 Operating Partnerships on behalf of Series 34, 11 Operating Partnerships on behalf of Series 35, 11 Operating Partnerships on behalf of Series 36, 7 Operating Partnerships on behalf of Series 37, 10 Operating Partnerships on behalf of Series 38, 9 Operating Partnerships on behalf of Series 39, 16 Operating Partnerships on behalf of Series 40, 21 Operating Partnerships on behalf of Series 41, 22 Operating Partnerships on behalf of Series 42, 23 Operating Partnerships on behalf of Series 43, 10 Operating Partnerships on behalf of Series 44, 30 Operating Partnerships on behalf of Series 45 and 15 Operating Partnerships on behalf of Series 46.

|The business objectives of the Limited Partnership are to:
|----------------------------------------------------------
|(1)                                                       
|(2)                                                       
|(3)                                                       
|(4)                                                       

The business objectives and investment policies of the Limited Partnership are described more fully on pages 49 to 61 of the Prospectus, as supplemented, under the caption "Investment Objectives and Acquisition Policies," which is incorporated herein by reference.

The Corporation has no operational history and capital needs.



EmployeesThe Corporation does not have any employees and does not perform any services.

|Item 3 | Quantitative and Qualitative Disclosure About Market Risk
|------ | ---------------------------------------------------------
|       |                                                          
|       | Not Applicable                                           

|Item 4 | Controls & Procedures
|------ | ---------------------
|       |                      
|       | (a)                  
|       |                      
|       |                      
|       | (b)                  
|       |                      

PART II - OTHER INFORMATION

|Item 1.  | Legal Proceedings                                          
|-------- | -----------------------------------------------------------
|         |                                                            
|         | None                                                       
|         |                                                            
|Item 1A. | Risk Factors                                               
|         |                                                            
|         | Not Applicable                                             
|         |                                                            
|Item 2.  | Unregistered Sales of Equity Securities and Use of Proceeds
|         |                                                            
|         | None                                                       
|         |                                                            
|Item 3.  | Defaults upon Senior Securities                            
|         |                                                            
|         | None                                                       
|         |                                                            
|Item 4.  | (Removed and Reserved.)                                    
|         |                                                            
|Item 5.  | Other Information                                          
|         |                                                            
|         | None                                                       
|         |                                                            
|Item 6.  | Exhibits                                                   
|         |                                                            
|         |                                                            
|         |                                                            
|         |                                                            
|         |                                                            
|         |                                                            
|         |                                                            
|         |                                                            
|         |                                                            







SIGNATURES

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

|                   |  | BCTC IV Assignor Corp.
|------------------ |  | ----------------------
|                   |  |                       
|Date: May 14, 2010 |  | By:                   
|                   |  |                       
|                   |  |                       

Pursuant to the requirements of the Securities Exchange Act of 1934,
this report has been signed below by the following persons on behalf of the
registrant and in the capacities and on the dates indicated:

|DATE:        | SIGNATURE:          | TITLE:                                                                   
|------------ | ------------------- | -------------------------------------------------------------------------
|             |                     |                                                                          
|May 14, 2010 | /s/ John P. Manning | Director, President (Principal Executive Officer), BCTC IV Assignor Corp.
|             | John P. Manning    
|             |                    
|             |                    
|             |                    



|DATE:        | SIGNATURE:       | TITLE:                                               
|------------ | ---------------- | -----------------------------------------------------
|             |                  |                                                      
|May 14, 2010 | /s/ Marc N. Teal | (Principal Financial Officer), BCTC IV Assignor Corp.
|             | Marc N. Teal    
|             |                 
|             |                 
|             |