<PAGE>   1
                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   FORM 10-Q/A
                                 AMENDMENT NO. 1

(Mark One)

[X]   QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934

For the quarterly period ended           MARCH 31, 1997

                                       or

[ ]   TRANSITION REPORT PURSUANT TO 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT
      OF 1934

For the transition period from                       to

Commission file number                       0-14551

                         CORPORATE PROPERTY ASSOCIATES 6
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                                               <C>       
         CALIFORNIA                                                                13-3247122
(State or other jurisdiction of incorporation or organization)    (I.R.S. Employer Identification No.)

50 ROCKEFELLER PLAZA, NEW YORK, NEW YORK                                        10020
(Address of principal executive offices)                                      (Zip Code)
</TABLE>

                                 (212) 492-1100
              (Registrant's telephone number, including area code)


   (Former name, former address and former fiscal year, if changed since last
                                    report)



      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.

                                                               [X] Yes    [ ] No


                APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY
                  PROCEEDINGS DURING THE PRECEDING FIVE YEARS:

      Indicate by check mark whether the registrant has filed all documents and
reports required to be filed by Section 12, 13 or 15(d) of the Securities
Exchange Act of 1934 subsequent to the distribution of securities under a plan
confirmed by a court.

                                                               [ ] Yes    [ ] No
<PAGE>   2
                         CORPORATE PROPERTY ASSOCIATES 6
                       - a California limited partnership

                                     PART I

                         Item 1. - FINANCIAL INFORMATION

                           CONSOLIDATED BALANCE SHEETS



<TABLE>
<CAPTION>
                                             December 31,      March 31,
                                                 1996            1997
                                             ------------     -----------
                                                (Note)        (Unaudited)
<S>                                          <C>              <C>        
      ASSETS:

Land, buildings and personal property,
   net of accumulated depreciation of
   $16,594,902 at December 31, 1996 and
   $17,020,169 at March 31, 1997             $ 47,968,552     $47,649,848
Net investment in direct financing leases      32,887,655      32,887,655
Cash and cash equivalents                       3,338,391       3,647,685
Notes receivable from affiliate                 1,151,000       1,151,000
Other assets                                    2,807,973       2,847,803
                                             ------------     -----------

        Total assets                         $ 88,153,571     $88,183,991
                                             ============     ===========


      LIABILITIES:

Mortgage notes payable                       $ 32,057,088     $31,769,217
Note payable                                   10,000,000      10,000,000
Accrued interest payable                          439,078         431,988
Accounts payable and accrued expenses             372,012         351,804
Accounts payable to affiliates                    131,275         166,959
Other liabilities                                 361,816         221,900
Deferred rental income                          3,544,624       3,483,333
                                             ------------     -----------
        Total liabilities                      46,905,893      46,425,201
                                             ------------     -----------


      PARTNERS' CAPITAL:

General Partners                                   (4,515)         29,956

Limited Partners (47,930 Limited
Partnership Units issued and outstanding)      41,252,193      41,728,834
                                             ------------     -----------   
        Total partners' capital                41,247,678      41,758,790
                                             ------------     -----------

        Total liabilities and
          partners' capital                  $ 88,153,571     $88,183,991
                                             ============     ===========
</TABLE>

The accompanying notes are an integral part of the consolidated financial
statements.


Note: The consolidated balance sheet at December 31, 1996 has been derived from
      the audited financial statements at that date.


                                      -2-
<PAGE>   3
                         CORPORATE PROPERTY ASSOCIATES 6
                       - a California limited partnership


                  CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)



<TABLE>
<CAPTION>
                                                  Three Months Ended
                                            March 31, 1996   March 31, 1997
                                            --------------   --------------
<S>                                         <C>              <C>       
Revenues:
  Rental income from operating leases         $1,302,939       $1,527,846
  Interest from direct financing leases        1,405,710        1,417,174
  Other interest income                           89,936           67,582
  Revenue of hotel operations                  1,135,887        1,206,821
  Other income                                                    126,985
                                              ----------       ----------
                                               3,934,472        4,346,408
                                              ----------       ----------

Expenses:
  Interest                                     1,039,515          956,725
  Depreciation                                   390,432          425,267
  General and administrative                     101,256          177,249
  Property expense                                46,844           54,192
  Amortization                                    57,559           68,664
  Operating expenses of
   hotel operations                              912,682          920,754
                                              ----------       ----------
                                               2,548,288        2,602,851
                                              ----------       ----------


   Income before gain on
     sale of real estate                       1,386,184        1,743,557

Gain on sale of real estate                       31,456
                                              ----------       ----------

   Net income                                 $1,417,640       $1,743,557
                                              ==========       ==========

Net income allocated to
  General Partners                            $   85,058       $  104,613
                                              ==========       ==========


Net income allocated to
  Limited Partners                            $1,332,582       $1,638,944
                                              ==========       ==========


Net income per Unit
  (47,930 Limited Partnership Units)          $    27.80       $    34.19
                                              ==========       ==========
</TABLE>

The accompanying notes are an integral part of the consolidated financial
statements.


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<PAGE>   4
                         CORPORATE PROPERTY ASSOCIATES 6
                       - a California limited partnership



                CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)


<TABLE>
<CAPTION>
                                                                Three Months Ended
                                                                      March 31,
                                                            ---------------------------
                                                                1996            1997
                                                            -----------     -----------
<S>                                                         <C>             <C>        
Cash flows from operating activities:
  Net income                                                $ 1,417,640     $ 1,743,557
  Adjustments to reconcile net income to net
    cash provided by operating activities:
    Depreciation and amortization                               447,991         493,931
    Other noncash items                                         (61,290)        (76,098)
    Gain on sales of real estate                                (31,456)
    Net change in operating assets and liabilities              142,073        (225,217)
                                                            -----------     -----------

     Net cash provided by operating activities                1,914,958       1,936,173
                                                            -----------     -----------

Cash flows from investing activities:
  Additional capitalized costs                               (1,762,598)       (106,563)
  Proceeds from sales of real estate                            257,527
                                                            -----------     -----------

     Net cash used in investing activities                   (1,505,071)       (106,563)
                                                            -----------     -----------

Cash flows from financing activities:
  Distributions to partners                                  (1,204,998)     (1,232,445)
  Proceeds from mortgage note payable                         6,000,000
  Prepayment of mortgage notes payable                       (4,257,315)
  Payments on mortgage principal                               (251,394)       (287,871)
  Deferred financing costs                                     (270,785)
                                                            -----------     -----------

     Net cash provided by (used in) financing activities         15,508      (1,520,316)
                                                            -----------     -----------

       Net increase in cash and cash equivalents                425,395         309,294

Cash and cash equivalents, beginning of period                3,476,915       3,338,391
                                                            -----------     -----------

       Cash and cash equivalents, end of period             $ 3,902,310     $ 3,647,685
                                                            ===========     ===========




Supplemental disclosure of cash flows information:

Interest paid                                               $ 1,046,085     $   963,815
                                                            ===========     ===========
</TABLE>

The accompanying notes are an integral part of the consolidated financial
statements.


                                      -4-
<PAGE>   5
                         CORPORATE PROPERTY ASSOCIATES 6
                       - a California limited partnership

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)





Note 1. Basis of Presentation:

The accompanying unaudited consolidated financial statements have been prepared
in accordance with generally accepted accounting principles for interim
financial information and with the instructions to Form 10-Q and Rule 10-01 of
Regulation S-X. Accordingly, they do not include all of the information and
footnotes required by generally accepted accounting principles for complete
financial statements. In the opinion of management, all adjustments (consisting
of normal recurring accruals) considered necessary for a fair presentation have
been included. For further information, refer to the financial statements and
footnotes thereto included in the Partnership's Annual Report on Form 10-K for
the year ended December 31, 1996.



Note 2. Distributions to Partners:

Distributions declared and paid to partners during the three months ended March
31, 1997 are summarized as follows:

<TABLE>
<CAPTION>
  Quarter Ended      General Partners    Limited Partners    Per Limited Partner Unit
-----------------    ----------------    ----------------    ------------------------
<S>                  <C>                 <C>                 <C>   
December 31, 1996         $70,142            $1,162,303              $24.25
                          =======            ==========              ======
</TABLE>



A distribution of $24.27 per Limited Partner Unit for the quarter ended March
31, 1997 was declared and paid in April 1997.




Note 3. Transactions with Related Parties:

For the three-month periods ended March 31, 1996 and 1997, the Partnership
incurred management fees of $27,101 and $28,476, respectively, and general and
administrative expense reimbursements of $26,542 and $46,607 respectively.
Management believes that ultimate payment of a preferred return to the General
Partners of $18,099, based upon cumulative proceeds of sales of assets, is
reasonably possible but not probable, as defined pursuant to Statement of
Financial Accounting Standards No. 5.

The Partnership, in conjunction with certain affiliates, is a participant in an
agreement for the purpose of renting and occupying office space. Under the
agreement, the Partnership pays its proportionate share of rent and other costs
of occupancy. Net expenses incurred for the three months ended March 31, 1996
and 1997 were $36,203 and $32,367 respectively.


                                      -5-
<PAGE>   6
                         CORPORATE PROPERTY ASSOCIATES 6
                       - a California limited partnership

      NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED) - (CONTINUED)




Note 4. Industry Segment Information:

The Partnership's operations consist primarily of the investment in and the
leasing of industrial and commercial real estate and the operation of three
hotel properties. For the three-month periods ended March 31, 1996 and 1997, the
Partnership earned its total real estate lease revenues (rental income plus
interest income from financing leases) as follows:

<TABLE>
<CAPTION>
                                        1996       %             1997       %
                                        ----      ---            ----      ---
<S>                                 <C>           <C>          <C>         <C>
Stoody Deloro Stellite, Inc.        $  558,548     21%         $558,548     19%
AP Parts Manufacturing, Inc.           421,303     16           459,134     16
Peerless Chain Company                 378,653     14           427,147     15
AutoZone, Inc.                         342,489     13           330,392     11
Kinney Shoe Corporation                168,192      6           241,235      8
Wal-Mart Stores, Inc.                  206,815      8           222,782      8
Anthony's Manufacturing Company,
 Inc.                                  219,000      8           219,000      7
Motorola, Inc.                         135,000      5           135,000      5
Harcourt General Corporation           116,875      4           116,875      4
Yale Security, Inc.                                             114,807      4
Lockheed Martin Corporation             73,250      3            77,500      2
Winn-Dixie Stores, Inc.                 42,600      1            42,600      1
Folger Adam Company                     45,924      1
                                    ----------    ---        ----------    ---
                                    $2,708,649    100%       $2,945,020    100%
                                    ==========    ===        ==========    ===
</TABLE>





Operating results of the three hotels for the three-month periods ended March
31, 1996 and 1997 are summarized as follows:

<TABLE>
<CAPTION>
                                             1996            1997
                                         -----------     -----------
<S>                                      <C>             <C>        
Revenue                                  $ 1,135,887     $ 1,206,821
Fees paid to hotel management company        (27,564)        (32,700)
Other operating expenses                    (885,118)       (888,054)
                                         -----------     -----------
Hotel operating income                   $   223,205     $   286,067
                                         ===========     ===========
</TABLE>


                                      -6-
<PAGE>   7
                         CORPORATE PROPERTY ASSOCIATES 6
                       - a California limited partnership





                                   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.


                                  CORPORATE PROPERTY ASSOCIATES 6
                                  - a California limited partnership

                                  By:  CAREY CORPORATE PROPERTY, INC.




    09/03/97                      BY:   /s/ Steven M. Berzin
----------------                       ---------------------------------
     Date                              Steven M. Berzin
                                       Executive Vice President and
                                       Chief Financial Officer
                                       (Principal Financial Officer)



    09/03/97                      BY:   /s/ Claude Fernandez
----------------                       ---------------------------------
     Date                              Claude Fernandez
                                       Executive Vice President and
                                       Chief Administrative Officer
                                       (Principal Accounting Officer)


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