EXHIBIT 23.1


            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM



Board of Directors and Stockholders
Mission West Properties, Inc.
Cupertino, California

We  hereby  consent  to the  incorporation  by  reference  in  the  Registration
Statement  on Form  S-8,  SEC File No.  333-80369,  and Form  S-8,  SEC File No.
333-123466,  of Mission West  Properties,  Inc. of our reports dated February 3,
2006, relating to the consolidated financial statements and the effectiveness of
Mission West Properties, Inc.'s internal control over financial reporting, which
appear in this Annual Report on Form 10-K. We also consent to the  incorporation
by  reference  of our report dated  February 3, 2006  relating to the  financial
statement schedules which appear in this Form 10-K.


                                                        \S\BDO Seidman, LLP


San Francisco, California
March 13, 2006

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