<PAGE>
 
================================================================================
                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                         ______________________________
                                  FORM 10-K/A

[X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934
     For the fiscal year ended December 31, 1997

                                       OR

[ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934
     For the transition period from              to

                        Commission File Number: 0-24720

                             BUSINESS OBJECTS S.A.
             (exact name of registrant as specified in its charter)

        The Republic of France                                NONE
(Jurisdiction of incorporation or organization)        (I.R.S. Employer
                                                        Identification No.)
                1 Square Chaptal, 92300 Levallois-Perret France
                    (Address of principal executive offices)

                                 (408) 953-6024
              (Registrant's telephone number, including area code)

  Securities registered or to be registered pursuant to Section 12(b) of the
  Act: None

                         ______________________________

  Securities registered or to be registered pursuant to Section 12(g) of the
  Act:

       Title of each class:        Name of each exchange on which registered:
       --------------------        ------------------------------------------
  American Depositary Shares, each
   representing one Ordinary Share            Nasdaq National Market
  Ordinary Shares                             Nasdaq National Market*

  * Not for trading, but only in connection with the American Depositary Shares.
                         ______________________________
  Securities for which there is a reporting obligation pursuant to Section 15(d)
of the Act: None
                         ______________________________

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
Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.  [    ]
<PAGE>
 
     The aggregate market value of the voting stock held by non-affiliates of
the registrant, based upon the closing sale price of the ADS on February 27,
1998 as reported on the National Market of The Nasdaq Stock Market, was
approximately $177,642,000. Shares of Common Stock held by each officer and
director and by each person who owns 5% or more of the outstanding Common Stock
have been excluded in that such persons may be deemed to be affiliates. This
determination of affiliate status is not necessarily a conclusive determination
for other purposes.

     The number of outstanding shares of each of the issuer's classes of capital
or common stock as of February 27, 1998 was 16,784,154 Ordinary Shares of FF1
nominal value, including 13,412,210 American Depositary Shares (as evidenced by
American Depositary Receipts), each corresponding to one Ordinary Share.

                      DOCUMENTS INCORPORATED BY REFERENCE

     The Registrant has incorporated by reference into Part III of this Form 10-
K portions of its Proxy Statement for Registrant's Annual Meeting of
Shareholders to be held June 18, 1998.

                           _________________________

     Unless otherwise stated, references herein to the "Company" or to "Business
Objects" are to Business Objects S.A. and its consolidated subsidiaries.

                           _________________________

                                  TRADEMARKS
                                        
     BusinessObjects, the Business Objects logo, BusinessQuery, BusinessMiner,
BusinessAnalyzer, Microcube, PowerReport, Rapid Deployment Template,
ReportScript, Semantically Dynamic, SmartSpace, Universe Repository and
WebIntelligence are registered trademarks of Business Objects S.A.  All other
trademarks or trade names referenced to in this Annual Report on form 10-K are
the property of their respective owners.

                          ___________________________

                               REPORTING CURRENCY
                                        
     All financial information contained in this document is expressed in United
States dollars, unless otherwise stated.

                          __________________________

                          AMERICAN DEPOSITARY SHARES
                                        
     Pursuant to a program sponsored by the Company, ordinary shares of the
Company (the "Shares") are traded in the United States in the form of American
Depositary Shares ("ADSs"), each ADS representing one Share placed on deposit
with The Bank of New York, as depositary (the "Depositary") and issued and
delivered by the Depositary through its principal office in New York City at 101
Barclay Street, New York, New York, 10286. Under the terms of the Deposit
Agreement (the "Deposit Agreement") dated September 22, 1994 and amended May 8,
1996, Shares may be deposited with the Paris office of Banque Paribas, as
custodian (the "Custodian"), or any successor or successors to such Custodian.
The Depositary provides a variety of services to investors, as more fully set
forth in the form of Deposit Agreement filed as an exhibit to the Company's
Registration Statement on Form F-6 filed with the Securities and Exchange
Commission on August 22, 1994.

     Under the original Deposit Agreement two Shares converted into one ADS.
Following the amendment of the Deposit Agreement on May 8, 1996, one Share
converts into one ADS. This had the effect of doubling the number of outstanding
ADSs, producing the same result as a 2-for-1 stock split. Except where otherwise
indicated, all ADS and per ADS information contained herein has been adjusted to
give effect to this amendment for all periods.
<PAGE>
 
     The undersigned Registrant hereby amends the Cover Page of its Annual
Report on Form 10-K for the year ended December 31, 1997 to report a change in
the date of the Company's Annual Meeting of Shareholders from June 3, 1998 to
June 18, 1998.


                                   SIGNATURES
                                        
     PURSUANT TO THE REQUIREMENTS OF SECTION 13 OR 15(D) 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.


  BUSINESS OBJECTS S.A.

  Date:  June 3, 1998                          By: /s/  BERNARD LIAUTAUD
                                                   ---------------------
                                                      Bernard Liautaud
                                                   Chairman of the Board,
                                                   President and Chief Executive
                                                   Officer


  Date:  June 3, 1998                          By: /s/  CLIFTON T. WEATHERFORD
                                                   ---------------------------
                                                      Clifton T. Weatherford
                                                      Chief Financial Officer
                                                     and Senior Group Vice
                                                     President