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

                                    FORM 11-K


[x]       Annual Report Pursuant to Section 15(D) of the Securities Exchange Act
          of 1934

For the fiscal year ended December 31, 2004
                          -----------------

                                       OR

[ ]       Transition  Report  Pursuant  to  Section  15(D) of the  Securities
          Exchange Act of 1934

For the transition period from  ____________  to  ____________.

Commission File Number:  1-10709


A.   Full title of the plan and the address of the plan, if different from that
     of the issuer named below:

                          PS 401(k) PROFIT SHARING PLAN
                               701 Western Avenue
                             Glendale, CA 91201-2349

B.   Name of issuer of the securities held pursuant to the plan and the address
     of its principal executive office:

                             PS BUSINESS PARKS, INC.
                               701 Western Avenue
                             Glendale, CA 91201-2349





                          PS 401(k) PROFIT SHARING PLAN

                              FINANCIAL STATEMENTS
                           AND SUPPLEMENTAL SCHEDULES



                                TABLE OF CONTENTS

                                                                        Page



Report of Independent Registered Public Accounting Firm                    1


Financial Statements:

  Statements of Net Assets Available
    for Plan Benefits                                                      2

  Statements of Changes in Net Assets
    Available for Plan Benefits                                            3

  Notes to Financial Statements                                        4 - 8


Supplemental Information:

  Schedule I - Schedule of Assets (Held at End of Year)                    9

  Schedule II - Schedule of Reportable Transactions                       10 





                                        1
             Report of Independent Registered Public Accounting Firm
             -------------------------------------------------------

To the Administrative Committee
PS 401(k) Profit Sharing Plan
Glendale, California

We have audited the  accompanying  statements  of net assets  available for plan
benefits of PS 401(k)  Profit  Sharing Plan (the "Plan") as of December 31, 2004
and 2003, and the related statements of changes in net assets available for plan
benefits for each of the years in the three year period ended December 31, 2004.
These financial statements are the responsibility of the Plan's management.  Our
responsibility  is to express an opinion on these financial  statements based on
our audits.

We conducted our audits in accordance  with the standards of the Public  Company
Accounting Oversight Board (United States). Those standards require that we plan
and  perform  the  audits to  obtain  reasonable  assurance  about  whether  the
financial  statements  are free of  material  misstatement.  An  audit  includes
examining,  on a test basis,  evidence supporting the amounts and disclosures in
the  financial  statements.  An audit also  includes  assessing  the  accounting
principles  used  and  significant  estimates  made  by  management,  as well as
evaluating the overall  financial  statement  presentation.  We believe that our
audits provide a reasonable basis for our opinion.

In our opinion,  the financial  statements  referred to above present fairly, in
all material respects, the net assets available for plan benefits of the Plan as
of December 31, 2004 and 2003, and the changes in net assets  available for plan
benefits for each of the years in the three year period ended  December 31, 2004
in conformity with accounting principles generally accepted in the United States
of America.

Our audits  were  conducted  for the  purpose of forming an opinion on the basic
financial  statements  taken as a whole.  The  supplemental  schedules of assets
(held at end of year)  and  reportable  transactions,  together  referred  to as
"supplemental information", are presented for the purpose of additional analysis
and  are  not a  required  part  of  the  basic  financial  statements  but  are
supplementary  information  required  by the  Department  of  Labor's  Rules and
Regulations for Reporting and Disclosure  under the Employee  Retirement  Income
Security Act of 1974. This supplemental information is the responsibility of the
Plan's  management.  The  supplemental  information  has been  subjected  to the
auditing procedures applied in the audits of the basic financial statements and,
in our opinion,  are fairly  stated in all material  respects in relation to the
basic financial statements taken as a whole.

LINK, MURREL & COMPANY

Irvine, California
May 25, 2005

                                       1




                          PS 401(k) PROFIT SHARING PLAN

                       STATEMENTS OF NET ASSETS AVAILABLE
                                FOR PLAN BENEFITS

                           December 31, 2004 and 2003




                                                                        2004                2003
                                                                  --------------         ------------
                              ASSETS

                                                                                           
  Investments at fair value.....................................  $58,377,895            $52,811,901

  Cash..........................................................       24,041                  1,972

  Receivables:
     Participant contributions..................................       96,350                 96,547
     Employer contributions.....................................      121,060                109,212
     Dividends..................................................      267,074                279,785
                                                                  --------------         ------------
  Total receivables.............................................      484,484                485,544
                                                                  --------------         ------------
  Total assets..................................................   58,886,420             53,299,417
                                                                  ==============         ============

                           LIABILITIES

  Accrued expenses..............................................       43,696                 33,369
                                                                  --------------         ------------
  Total liabilities.............................................       43,696                 33,369
                                                                  --------------         ------------
  Net assets available for plan benefits........................  $58,842,724            $53,266,048
                                                                  ==============         ============



                            See accompanying notes.
                                       2




                          PS 401(k) PROFIT SHARING PLAN

                       STATEMENTS OF CHANGES IN NET ASSETS
                           AVAILABLE FOR PLAN BENEFITS

              For the Years Ended December 31, 2004, 2003 and 2002




                                                                 2004              2003              2002
                                                            --------------    -------------   ----------------
ADDITIONS TO NET ASSETS ATTRIBUTED TO:

      Investment income:
        Net appreciation (depreciation) in fair value of
                                                                                                 
           investments....................................   $  7,082,444      $  9,869,662    $  (4,438,271)
        Interest income...................................         62,308            25,244             8,395
        Dividend income...................................      1,070,226         1,253,965         1,493,190
                                                            --------------    -------------   ----------------
                                                                8,214,978        11,148,871        (2,936,686)
      Contributions:
        Participant.......................................      2,664,501         2,822,413         2,935,842
        Employer..........................................      2,743,248         2,607,288         2,457,646
                                                            --------------    -------------   ----------------
                                                                5,407,749         5,429,701         5,393,488
                                                            --------------    -------------   ----------------
      Total additions.....................................     13,622,727        16,578,572         2,456,802

DEDUCTIONS FROM NET ASSETS ATTRIBUTED TO:

      Benefits paid to participants.......................      7,982,392         4,787,947         3,328,933
      Administrative expenses.............................         63,659           116,672           154,071
                                                            --------------    -------------   ----------------
      Total Deductions....................................      8,046,051         4,904,619         3,483,004
                                                            --------------    -------------   ----------------
  Net increase (decrease) in net assets available for
     benefits.............................................      5,576,676        11,673,953        (1,026,202)
  Net assets available for benefits - beginning of year...     53,266,048        41,592,095        42,618,297
                                                            --------------    -------------   ----------------
  Net assets available for benefits - end of year.........   $ 58,842,724      $ 53,266,048    $  41,592,095
                                                            ==============    =============   ================



                            See accompanying notes.
                                       3



                          PS 401(k) PROFIT SHARING PLAN
                          NOTES TO FINANCIAL STATEMENTS
                                December 31, 2004


1.       Summary of Significant Accounting Principles
         --------------------------------------------

         Basis of Presentation

         PS 401(k) Profit Sharing Plan (the "Plan")  encompasses Public Storage,
         Inc., PS Business  Parks,  Inc. and their majority  owned  subsidiaries
         (the "Company").

         Basis of Accounting
         -------------------

         The  financial  statements  of the Plan are prepared  under the accrual
         basis of accounting.

         Estimates
         ---------

         The  preparation of financial  statements in conformity with accounting
         principles  generally accepted in the United States of America requires
         the Plan  administrator  to make estimates and assumptions  that affect
         certain reported amounts and disclosures.  Accordingly,  actual results
         may differ from those estimates.

         Income Tax Status
         -----------------

         The Plan obtained its latest determination letter on March 14, 2003, in
         which the  Internal  Revenue  Service  stated  that the  Plan,  as then
         designed,  was in compliance  with the applicable  requirements  of the
         Internal  Revenue Code.  The Plan has been amended since  receiving the
         determination  letter.  However,  the Plan administrator and the Plan's
         tax  counsel  believe  that the Plan is  currently  designed  and being
         operated in compliance with the applicable requirements of the Internal
         Revenue  Code.  Therefore,  no  provision  for  income  taxes  has been
         included in the Plan's financial statements.

         Investment Valuation
         --------------------

         Investments in cash equivalents  (liquid funds,  money market funds and
         time  deposits)  are valued at cost,  which  approximates  fair  value.
         Investments  in  mutual  funds  are  stated  at fair  value.  All other
         securities  are  valued  at the last  reported  sale  price on the last
         business day of the Plan year or at the quoted market  price.  Interest
         income  is  recognized  when  earned.  Dividends  are  recorded  on the
         ex-dividend date.

2.       Description of the Plan
         -----------------------

         The   following   description   of  the  plan   provides  only  general
         information.  Participants should refer to the Summary Plan Description
         for a more  complete  description  of  the  Plan's  provisions.  Note 9
         contains  information  on key changes to the Plan which were  effective
         January 1, 2005, and impact the topics on eligibility and the Company's
         contribution.

         The PS 401(k) Profit  Sharing Plan is a defined  contribution  plan for
         the  benefit  of all  permanent  employees  of  the  Company  who  have
         completed  at least one year of service  and  attained 21 years of age.
         The Plan is subject to the provisions of the Employee Retirement Income
         Security  Act of  1974  (ERISA).  Although  it has  not  expressed  the
         intention  to do so, the  Company has the right to  terminate  the Plan
         subject to ERISA  provisions.  The Plan allows  interim  allocations of
         Company contributions and earnings or losses of trust fund assets among
         participants. Major provisions of the Plan, are as follows:

         Contributions
         -------------

         Employee  contributions  to  the  Plan  (voluntary  contributions)  are
         deferrals  of  the  employee's   compensation  made  through  a  direct
         reduction of compensation  in each payroll  period.  The maximum annual
         tax deferred contribution,  excluding catch-up contributions, amount is
         limited to $13,000 for 2004 and $12,000 for 2003. Participants may also
         contribute  amounts  representing  distributions  from other  qualified
         benefit or defined  contribution  plans. The Company  contributes 3% of
         the  employee's   compensation   for  all  participants  in  the  Plan.
         Additional  profit sharing  amounts may be contributed at the option of
         the Company's board of directors.  Contributions are subject to certain
         limitations.

                                       4



                          PS 401(k) PROFIT SHARING PLAN
                          NOTES TO FINANCIAL STATEMENTS
                                December 31, 2004


         Participant Accounts
         --------------------

         Each   participant's   account  is  credited  with  the   participant's
         contribution,  the guaranteed  Company  contribution and allocations of
         (a) the Company's  profit sharing  contribution  and (b) Plan earnings,
         and charged with an allocation of administrative expenses.  Allocations
         are based on participant earnings or account balances,  as defined. The
         benefit to which a  participant  is entitled is the benefit that can be
         provided from the participant's vested account.

         Vesting
         -------

         Employee deferrals and the 3% guaranteed Company  contribution are 100%
         vested  and   non-forfeitable.   Profit  sharing  Company  contribution
         balances vest over a seven year period.

         Generally,   each  participant's  account  becomes  10  percent  vested
         (non-forfeitable)  after two years of service (as defined),  20 percent
         after  three  years of service  and an  additional  20 percent for each
         additional year of service thereafter.

         Upon death, severance by reason of disability, or the attainment of the
         participant's sixty-fifth birthday, a participant automatically becomes
         fully  vested to the  extent of the  balance in their  account.  In the
         event  the  Plan  is  terminated  or   contributions   are   completely
         discontinued, each participant becomes fully vested.

         Investment Options
         ------------------

         For the year ended  December 31, 2004,  upon  enrollment in the Plan, a
         participant may direct contributions in any of the following twenty-two
         investment options:

      1.  Highmark Div. Money Market       12. American Funds Growth Fund R3
      2.  Strong Government Securities     13. AIM Opportunities A
      3.  BGI Lifepath Income Fund R       14. AIM Small CAP Growth A
      4.  BGI Lifepath 2010 Class R        15. Oakmark International II
      5.  BGI Lifepath 2020 Class R        16. Fidelity Advisor Equity Growth
      6.  BGI Lifepath 2030 Class R        17. Ivy Science & Technology Y
      7.  BGI Lifepath 2040 Class R        18. PIMCO Real Return Bond
      8.  MFS Value A                      19. Public Storage Common Stock
      9.  Federated Capital Appreciation   20. Public Storage Preferred Stock
      10. Dreyfus S&P 500 Index            21. P.S. Business Parks Stock
      11. Janus Adv CAP Appreciation       22. Scudder Real Estate

         Participants may change their investment options at any time.

         Distributions from the Trust Fund
         ---------------------------------

         Distributions  of  each  participant's   vested  account  balance  upon
         severance  or death are made in a single  lump sum  payment;  or if the
         participant's  vested account balance  exceeds  $5,000,  payment may be
         deferred until April 1st of the calendar year in which the  participant
         reaches 70 1/2 years of age.

         Additionally, the Plan provides for hardship distributions (as defined)
         at the discretion of the Plan Administrative Committee.

                                       5



                          PS 401(k) PROFIT SHARING PLAN
                          NOTES TO FINANCIAL STATEMENTS
                                December 31, 2004


         Generally, distributions are made no later than 60 days after the close
         of the Plan year in which the  participant  becomes  eligible  for such
         distributions.  Under certain  circumstances,  participants enrolled in
         the Plan prior to and including December 31, 1983 may elect alternative
         distribution methods.

         Forfeited Accounts
         ------------------

         Forfeitures of profit sharing  contributions will be used to reduce the
         Company's  contribution  for profit sharing  contributions,  guaranteed
         Company contributions or guaranteed matching contributions. At December
         31,  2004 and 2003,  forfeited  nonvested  amounts  were  approximately
         $1,254,000 and $729,000, respectively. These accounts will be allocated
         to  individual  participant's  accounts  in the  ratio  that  each such
         eligible participant's  compensation bears to the total compensation of
         all such eligible  participants  in the plan year the  forfeitures  are
         used.

3.       Investments
         -----------

         Union Bank has  custody of the  investments  under a  non-discretionary
         trust  agreement with the Plan.  The following  table presents the fair
         value of investments.  Investments  that represent five percent (5%) or
         more of the Plan's net assets are separately identified.  Quoted market
         prices are used to value investments.

         The fair value of investments held by the Plan are summarized below:




                                                 At December 31, 2004             At December 31, 2003
                                            ------------------------------   ------------------------------
                                               Shares           Amount          Shares           Amount
                                            -------------  ---------------   -------------   --------------
                                                                                           
         Money Market Funds                    8,498,252     $  8,498,252       6,235,936     $  6,235,936
         Mutual Funds                          1,021,263       22,777,852       1,096,492       22,968,239
         Equity Securities:
            Public Storage, Inc. Common          409,794       22,846,009         453,948       19,655,222
            Public Storage, Inc. Preferred       126,894        3,643,129         115,441        3,451,686
            PS Business Parks, Inc.
            Common                                13,584          612,653          11,520          500,818
                                            -------------  ---------------   -------------   --------------
                 Total Equity Securities         550,272       27,101,791         580,909       23,607,726
                                            -------------  ---------------   -------------   --------------
         Total Investments                    10,069,787     $ 58,377,895       7,913,337     $ 52,811,901
                                            =============  ===============   =============   ==============



         The following  presents the fair value of  investments  at December 31,
         2004 and 2003 that  represent  five  percent (5%) or more of the Plan's
         net assets:

                                                  2004                 2003
                                            ----------------    ----------------
         Money Market Funds                 $     8,498,252     $      6,235,936
         Mutual Funds:
            Dreyfus S&P 500 Index           $     8,615,718     $     10,230,371
            Strong Government Securities    $     3,230,585     $      4,191,198
         Public Storage, Inc. Common        $    22,846,009     $     19,655,222
         Public Storage, Inc. Preferred     $     3,643,129     $      3,451,686

         During 2004, 2003, and 2002 the Plan's investments (including gains and
         losses on investments bought and sold, as well as held during the year)
         appreciated (depreciated) in value as follows:

                                       6



                          PS 401(k) PROFIT SHARING PLAN
                          NOTES TO FINANCIAL STATEMENTS
                                December 31, 2004





                                                       2004              2003              2002
                                                 ---------------    -------------    ---------------
                                                                                       
         Mutual Funds........................    $    1,931,914     $   4,260,474    $  (3,946,588)
         Common Stock........................         5,150,530         5,609,188         (491,683)
                                                 ---------------    -------------    ---------------
             Totals                              $    7,082,444     $   9,869,662    $  (4,438,271)




4.       Plan Administration
         -------------------

         The Company's Board of Directors appoints a committee to administer the
         Plan.  The Plan  Administrative  Committee  is now  comprised  of seven
         officers and managers of the Company.

         For the plan years ended  December  31, 2004,  2003 and 2002,  the Plan
         paid  certain  trustee and  administrative  expenses  incurred  for the
         administration  of the Plan.  The Company  directly  paid for all other
         expenses related to the Plan.

5.       Benefits Owed To Terminated Participants
         ----------------------------------------

         For  financial   reporting   purposes,   disbursements   to  terminated
         participants  are  reported  when the check is  written.  Approximately
         $20,590,000  and  $16,200,000  were owed to terminated  participants at
         December 31, 2004 and 2003, respectively.

6.       Related Party Transactions
         --------------------------

         Certain  Plan  investment  options are the  Company's  securities.  The
         Company is the plan  sponsor as defined by the Plan.  The Plan held the
         following shares in the Company's securities:




                                                 At December 31, 2004             At December 31, 2003
                                             -----------------------------    -----------------------------
                                               Shares           Amount          Shares           Amount
                                             ------------   --------------    -----------    --------------
                                                                                           
         Public Storage, Inc. Common             409,794     $ 22,846,009         453,948     $ 19,655,222
         Public Storage, Inc. Preferred          126,894        3,643,129         115,441        3,451,686
         PS Business Parks, Inc. Common           13,584          612,653          11,520          500,818

         Totals                                  550,272     $ 27,101,791         580,909     $ 23,607,726



7.       Risks and Uncertainties
         -----------------------

         The Plan provides for various  investment options in any combination of
         equity,  fixed  income,  and other  investment  securities.  Investment
         securities are exposed to various risks, such as interest rate, market,
         and credit. Due to the level of risk associated with certain investment
         securities and the level of uncertainty related to changes in the value
         of  investment  securities,  it is at least  reasonably  possible  that
         changes in risks in the near term could materially affect participants'
         account  balances  and the amounts  reported in the  statements  of net
         assets  available  for  benefits  and the  statement  of changes in net
         assets available for benefits.

8.       Concentrations
         --------------

         Investments in the Company's securities comprised  approximately of 46%
         and 45% of the Plan's  total  investments  as of December  31, 2004 and
         2003, respectively.

                                       7



                          PS 401(k) PROFIT SHARING PLAN
                          NOTES TO FINANCIAL STATEMENTS
                                December 31, 2004


9.       Plan Amendments
         ---------------

         Effective  January 1, 2005,  the Plan was  amended to  incorporate  the
         following changes:

         o An employee is eligible to participate in the Plan if he or she is at
           least 21 years old and has completed 30 days of employment.

         o The Company will no longer offer the  guaranteed  three  percent (3%)
           contribution of compensation to each participant.  o The Company will
           contribute  one dollar ($1.00) for each dollar saved by a participant
           up to three percent (3%) of compensation.

         o The Company will also contribute an additional fifty cents ($.50) for
           each dollar that each  participant  saves in excess of three  percent
           (3%)  of  compensation  but  not  more  than  five  percent  (5%)  of
           compensation. The matching contribution is 100% vested.

                                       8




                            SUPPLEMENTAL INFORMATION

                                   SCHEDULE I

                          PS 401(k) PROFIT SHARING PLAN
                              SCHEDULE H, LINE 4i -
                    SCHEDULE OF ASSETS (HELD AT END OF YEAR)
                                December 31, 2004

                   Employer Identification Number: 95-3551121
                                Plan Number: 001




(a)                              (b)                                     (c)                     (d)             (e)
                                                              Description of investment
                                                               including maturity date,
                                                             rate of interest, collateral                        Current
      Identity of issue, borrower, lessor, or similar party      par or maturity date          Cost               Value 
-----------------------------------------------------------  ---------------------------     -----------    -------------
                          MONEY MARKET ACCOUNT
                                                                                                            
           Highmark Div. Money Market                               Money Market             $8,498,252     $  8,498,252

                              MUTUAL FUNDS
           Aim Investment  - Opportunities                          Mutual Fund                       **         167,463
           Aim Investment -  Small Cap Growth A                     Mutual Fund                       **       1,435,303
           American Funds Group - Growth Fund of
             America R3                                             Mutual Fund                       **         251,509
           Barclays Global Investors - LifePath Income              Mutual Fund                       **          20,666
           Barclays Global Investors - LifePath 2010 Class R        Mutual Fund                       **         241,302
           Barclays Global Investors - LifePath 2020 Class R        Mutual Fund                       **           7,155
           Barclays Global Investors - LifePath 2030 Class R        Mutual Fund                       **          36,130
           Barclays Global Investors - LifePath 2040 Class R        Mutual Fund                       **           6,293
           Dreyfus Investment - S&P 500 Index                       Mutual Fund                       **       8,615,718
           Federated Investment - Capital Appreciation A            Mutual Fund                       **       2,323,630
           Fidelity Advisor Investment - Equity Growth              Mutual Fund                       **           8,069
           Ivy - Science & Technology Y                             Mutual Fund                       **       1,084,153
           Janus Advisor Funds - Capital Appreciation A             Mutual Fund                       **       2,832,518
           MFS Investment - Value A                                 Mutual Fund                       **       1,418,745
           Oakmark Funds - International II                         Mutual Fund                       **         774,384
           PIMCO Investment - Real Return Bond                      Mutual Fund                       **         304,558
           Scudder Investment - Real Estate                         Mutual Fund                       **          19,671
           Strong Funds - Government Securities Inv.                Mutual Fund                       **       3,230,585
                                                                                                            --------------
        Total Mutual Funds                                                                                    22,777,852

                            Equity Securities
     *     Public Storage, Inc. Common Stock                        Common Stock                      **      22,846,009
     *     Public Storage, Inc. Preferred Stock                     Preferred Stock                   **       3,643,129
     *     PS Business Parks, Inc. Common Stock                     Common Stock                      **         612,653
                                                                                                            --------------
        Total Equity Securities                                                                               27,101,791
                                                                                                            --------------
        Total Investments                                                                                   $ 58,377,895
                                                                                                            ==============



*  Indicates a party-in-interest of the Plan.

** Pursuant to paragraph 2520.103-11, specifically, the special rule for certain
   participant  directed  transactions cost information is omitted as the Plan's
   investments are participant directed.

                                       9




                            SUPPLEMENTAL INFORMATION

                                   SCHEDULE II

                          PS 401(k) PROFIT SHARING PLAN
                              SCHEDULE H, LINE 4j -
                       SCHEDULE OF REPORTABLE TRANSACTIONS
                                December 31, 2004

                   Employer Identification Number: 95-3551121
                                Plan Number: 001



A schedule of reportable transactions has not been presented because there were
no such transactions noted for the year ended December 31, 2004.

                                       10




                                   SIGNATURES

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
trustees (or other persons who administer  the employee  benefit plan) have duly
caused this annual report to be signed on its behalf by the undersigned hereunto
duly authorized.

                                    PS 401(k) PROFIT SHARING PLAN

Date: July 11, 2005

                                    By: /s/ Alan Herd
                                        -------------
                                            Alan Herd
                                            Chairman, Administrative Committee