MISSION WEST PROPERTIES, INC.
                    10050 Bandley Drive, Cupertino, CA 95014
                        Ph. 408-725-0700 Fax 408-725-1626


November 1, 2005

Mr. Josh Forgione
Staff Accountant
United States Securities and Exchange Commission
100 F Street, N.E.
Washington, D.C. 20549

         Re: Mission West Properties, Inc.
         Response to Comments from the SEC on Form 10-K for Fiscal Year Ended
         December 31, 2004
         Filed March 16, 2005
         File No. 0-25235

Dear Mr. Forgione:

This  letter  sets  forth  responses  of  Mission  West  Properties,  Inc.  (the
"Company") to your comments relating to the Company's Annual Report on Form 10-K
contained in your letter dated September 20, 2005. The Staff comment is repeated
in capitalized  letters below, and the Company's  response  appears  immediately
beneath each comment.

FORM 10-K FOR THE YEAR ENDED DECEMBER 31, 2004

ITEM 15. EXHIBITS,  FINANCIAL  STATEMENT SCHEDULES AND REPORTS ON FORM 8-K, PAGE
         88

     1.   WE NOTE YOUR  RESPONSE TO COMMENT  FIVE IN OUR LETTER DATED AUGUST 31,
          2005.  WE  REISSUE  OUR  COMMENT  AND  REQUEST  THAT YOU  REVISE  YOUR
          CERTIFICATIONS  FILED AS EXHIBITS  31.1,  31.2 AND 31.3 TO REFLECT THE
          LANGUAGE EXACTLY AS SET FORTH IN ITEM 601(b)(31) OF REGULATION S-K.

          In response to this  comment,  as well as comment no. 4 in your letter
          dated  October 21, 2005, we will file a Form 10-K/A for the year ended
          December  31,  2004 and revise our  certifications  filed as  Exhibits
          31.1,  31.2 and 31.3 to reflect the  language  exactly as set forth in
          Item 601(b)(31) of Regulation S-K.

     In connection with the foregoing responses to your comments, the Registrant
acknowledges:

     -    Company is responsible for the adequacy and accuracy of the disclosure
          in the filing;


     -    SEC staff  comments or changes to  disclosure in response to SEC staff
          comments do not  foreclose the SEC from taking any action with respect
          to the filing; and
     -    Company  may  not  assert  SEC  staff  comments  as a  defense  in any
          proceeding  initiated  by the  SEC or any  person  under  the  federal
          securities laws of the United States.

Sincerely,
Mission West Properties, Inc.
/s/ Carl E. Berg
Carl E. Berg
Chairman and CEO



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