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




                                    FORM 8-K

                                 CURRENT REPORT




                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

          Date of Report (Date of earliest event reported): May 15, 2006

                             PS BUSINESS PARKS, INC.
                          PS 401(k) Profit Sharing Plan
             (Exact Name of Registrant as Specified in its Charter)


          California                        1-10709                95-4300881
(State or Other Jurisdiction of     (Commission File Number)    (I.R.S. Employer
Incorporation) Identification No.)

 701 Western Avenue, Glendale, California                   91201-2349
 (Address of Principal Executive Offices)                   (Zip Code)

                                 (818) 244-8080
              (Registrant's telephone number, including area code)

Check the  appropriate  box below if the Form 8-K is intended to  simultaneously
satisfy  the filing  obligation  of the  registrant  under any of the  following
provisions:

|_|  Written communication pursuant to Rule 425 under the Securities Act (17 CFR
     230.425)

|_|  Soliciting  material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
     240.14a-12)

|_|  Pre-commencement   communications  pursuant  to  Rule  14d-2(b)  under  the
     Exchange Act (17 CFR 240.14d-2(b))

|_|  Pre-commencements  communications  pursuant  to  Rule  13e-4(c)  under  the
     Exchange Act (17 CFR 240.13e-4(c))





RETIREMENT PLAN CERTIFYING ACCOUNTANT

Item 4.01 Changes in Retirement Plan's Certifying Accountant

      On May 15, 2006, the Chairman of the Audit Committee of PS Business Parks,
Inc.,  approved  the  appointment  of  Ernst  &  Young,  LLP as the  independent
registered public accounting firm for PS 401(k) Profit Sharing Plan (the "Plan")
for the fiscal year December 31, 2006.

      During  the two most  recent  fiscal  years and the  interim  period  from
January 1, 2006  through May 3, 2006,  neither the Plan nor anyone on its behalf
has consulted with Ernst & Young,  LLP regarding  either (i) the  application of
accounting principles to a specified transaction,  either completed or proposed;
or the type of audit  opinion  that might be  rendered  on the Plan's  financial
statements,  and  neither a written  report  was  provided  to the Plan nor oral
advice was provided that Ernst & Young,  LLP  concluded was an important  factor
considered by the Plan in reaching a decision as to any accounting,  auditing or
financial  reporting  issue;  or (ii)  any  matter  that  was the  subject  of a
disagreement  (as that term is defined in Item 304  (a)(1)(iv) of Regulation S-K
and the related  instructions  to Item 304 of  Regulation  S-K) or a  reportable
event (as that term is defined in Item 304 (a)(1)(v) of Regulation S-K).

                                    SIGNATURE

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrants  have duly caused  this  report to be signed on their  behalf by the
undersigned hereunto duly authorized.

Date: May 16, 2006
PS 401(k) Profit Sharing Plan

By:      /s/ John S. Baumann
         -------------------
         John S. Baumann
         On behalf of the Administrative Committee