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                                  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): FEBRUARY 21, 2002



                          TESORO PETROLEUM CORPORATION
             (Exact name of registrant as specified in its charter)



<Table>
                                                                    
               DELAWARE                              1-3473                          95-0862768
     (State or other jurisdiction           (Commission File Number)      (IRS Employer Identification No.)
           of incorporation)

                        300 CONCORD PLAZA DRIVE                                      78216-6999
                          SAN ANTONIO, TEXAS                                         (Zip Code)
               (Address of principal executive offices)
</Table>




       Registrant's telephone number, including area code: (210) 828-8484




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ITEM 5. OTHER EVENTS

         On February 21, 2002, Tesoro Petroleum Corporation ("Tesoro") issued a
press release (the "Press Release") announcing Tesoro's first quarter 2002
earnings update. The foregoing is qualified by reference to the Press Release
which is filed as Exhibit 99.1 to the Current Report on Form 8-K and is
incorporated herein by reference.

         The information presented may contain forward-looking statements and
certain assumptions upon which such forward-looking statements are in part
based. Numerous important factors, including those factors identified as Risk
Factors and Investment Considerations in Tesoro's Annual Report on Form 10-K and
other of the Company's filings with the Securities and Exchange Commission, and
the fact that the assumptions set forth in the presentation data could prove
incorrect, could cause actual results to differ materially from those contained
in such forward-looking statements.

ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS

         (a)      Financial statements of businesses acquired.

                  Not applicable.

         (b)      Pro forma financial information.

                  Not applicable.

         (c)      Exhibits.

                  99.1     Press Release issued on February 21, 2002 by Tesoro
                           Petroleum Corporation.





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                                   SIGNATURES


         Pursuant to the requirements of the Securities Exchange Act of 1934, as
amended, the Registrant has duly caused this report to be signed on its behalf
by the undersigned hereunto duly authorized.


Date:    February 21, 2002


                                         TESORO PETROLEUM CORPORATION




                                         By:  /s/ Gregory A. Wright
                                            ------------------------------
                                                  Gregory A. Wright
                                                Senior Vice President,
                                              and Chief Financial Officer




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                                INDEX TO EXHIBITS


<Table>
<Caption>
EXHIBIT
NUMBER                            DESCRIPTION
- -------                           -----------
            
  99.1         Press Release issued on February 21, 2002 by Tesoro Petroleum
               Corporation.
</Table>






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