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

                                  FORM 10-K/A
                                AMENDMENT NO. 1

(Mark One)

[X]     Annual report pursuant to section 13 or 15(d) of the Securities Exchange
        Act of 1934

        For the Fiscal Year ended June 30, 2001

[ ]     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: 1-7134

                             MERCURY AIR GROUP, INC.
             (Exact Name of Registrant as Specified in Its Charter)

            DELAWARE                                 95-4836590
 (State or Other Jurisdiction of        (I.R.S. Employer Identification Number)
  Incorporation or Organization)

              5456 McConnell Avenue, Los Angeles, California 90066
--------------------------------------------------------------------------------
               (Address of Principal Executive Offices) (Zip Code)

Registrant's Telephone Number, Including Area Code: (310) 827-2737

Securities Registered Pursuant to Section 12(b) of the Act:


<TABLE>
<CAPTION>
                                                Name of Each Exchange on
        Title of Each Class                         Which Registered
        -------------------                     ------------------------
<S>                                            <C>
     Common Stock - Par Value $.01              American Stock Exchange
                                                 Pacific Stock Exchange
</TABLE>

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. Yes [X] 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. Yes [ ] No [X.]

        As of September 26, 2001, 6,576,680 shares of the Registrant's Common
Stock were outstanding. Of these shares, 2,058,113 shares were held by persons
who may be deemed to be affiliates. The 4,518,567 shares held by non-affiliates
as of September 26, 2001 had an aggregate market value (based on the closing
price of these shares on the American Stock Exchange of $4.50 a share) of
$20,335,552. As of September 26, 2001, there were no non-voting shares of common
stock outstanding.

                       DOCUMENTS INCORPORATED BY REFERENCE

        Portions of the Proxy Statement which is to be distributed in connection
with the Annual Meeting of Shareholders to be held in November 2001 are
incorporated by reference into Part III of this Form 10-K.


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                   (The Exhibit Index May Be Found at Page 25)


<PAGE>   2
Explanatory Note

This electronic report on Form 10-K/A is being filed solely for the purpose of
including Exhibit 23.1.
<PAGE>   3
Explanatory Note

This Form 10K/A is being filed solely for the purpose of including Exhibit 23.1.

Item 14 (a) Exhibits and Exhibit List

            All exhibits to this Form 10-K/A except those designated with two
            asterisks (**) which are filed herewith and those designated with
            three asterisks (***) which were filed with the initial filing of
            this Form 10-K on September 28, 2001 have previously been filed with
            the Commission, as referenced, and pursuant to 17 C.F.R. Section
            230.411 are incorporated by reference herein.


<TABLE>
<CAPTION>
 EXHIBIT
    NO.                             DESCRIPTION
---------                           -----------
<S>          <C>
   2.1        Agreement and Plan of Merger adopted January 9, 2001. (17)

   2.2        Certificate of Merger. (17)

   3.1        Bylaws of Company adopted January 9, 2001. (17)

   3.2        Certificate of Incorporation. (17)

   4.1        Loan Agreement between California Economic Development Financing
              Authority and Mercury Air Group, Inc. relating to $19,000,000
              California Economic Development Financing Authority Variable Rate
              Demand Airport Facilities Revenue Bonds, Series 1998 (Mercury Air
              Group, Inc. Project) dated as of April 1, 1998. (2)

   4.2        Securities Purchase Agreement dated September 10, 1999 by and
              among Mercury Air Group, Inc. and J.H. Whitney Mezzanine Fund,
              L.P. (12)

   4.3        Amendment No. 1 dated as of September 30, 2000 by and between J.H.
              Whitney Mezzanine, L.P. and Mercury Air Group, Inc. to the
              Securities Agreement. (16)

   4.4        Waiver and Consent Agreement dated as of December 29, 2000 among
              Mercury Air Group, Inc. and J.H. Whitney Mezzanine Fund, L.P. (17)

   4.5        Waiver and Consent Agreement dated as of July 2, 2001 among
              Mercury Air Group, Inc. and J.H. Whitney Mezzanine Fund, L.P.***

   4.6        Waiver Agreement dated as of September 25, 2001 among Mercury Air
              Group, Inc. and J.H. Whitney Mezzanine Fund, L.P.***

   10.1       Company's 1990 Long-Term Incentive Plan. (4)*

   10.2       Company's 1990 Directors Stock Option Plan. (1)*

   10.3       Lease for 6851 West Imperial Highway, Los Angeles, California. (3)

   10.4       Memorandum Dated September 15, 1997 regarding Summary of Officer
              Life Insurance Policies with Benefits Payable to Officers or Their
              Designated Beneficiaries. (8)*

   10.5       Employment Agreement dated November 15, 1994 between the Company
              and Joseph Czyzyk. (9)*

   10.6       Non-Qualified Stock Option Agreement dated March 21, 1996, by and
              between Frederick H. Kopko and Mercury Air Group, Inc. (6) *

   10.7       Company's 1998 Long-Term Incentive Plan. (10) *

   10.8       Company's 1998 Directors Stock Option Plan. (10) *

   10.9       Amendment to Employment Agreement by and between Mercury Air
              Group, Inc. and Joseph A. Czyzyk dated October 15, 1998. (11) *

   10.10      Amendment No. 2 to Employment Agreement by and between Mercury Air
              Group, Inc. and Joseph A. Czyzyk dated April 12, 1999. (11) *

   10.11      Revolving Credit and Term Loan Agreement dated as of March 2, 1999
              by and among Mercury Air Group, Inc., The Banks listed on Schedule
              1 thereto, and The Fleet National Bank f/k/a BankBoston, N.A., as
              Agent. (11)

   10.12      First Amendment to Revolving Credit and Term Loan Agreement dated
              as of September 10, 1999. (14)

   10.13      Second Amendment to Revolving Credit and Term Loan Agreement dated
              as of March 31, 2000. (14)

   10.14      Third Amendment, Waiver and Consent to Revolving Credit and Term
              Loan Agreement dated as of August 11, 2000. (14)

   10.15      The Company's 401(k) Plan consisting of CNA Trust Corporation.
              Regional Prototype Defined Contribution Plan and Trust and
              Adoption Agreement. (14)*

   10.16      Amendment No. 3 to Employment Agreement by and between Mercury Air
              Group, Inc. and Joseph A. Czyzyk dated September 11, 2000. (15)*

   10.17      Employment Agreement dated July 31, 2000 between the Company and
              Dr. Philip J. Fagan. (15)*

   10.18      Fourth Amendment to Revolving Credit and Term Loan Agreement dated
              as of November 14, 2000. (16)
</TABLE>



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<PAGE>   4

<TABLE>
<CAPTION>
 EXHIBIT
    NO.                             DESCRIPTION
---------                           -----------
<S>          <C>
   10.19      Amendment No. 1 to Mercury Air Group, Inc. 1998 Long-Term
              Incentive Option Plan as of August 22, 2000. (16)*

   10.20      Amendment No. 1 to Mercury Air Group, Inc. 1998 Directors Stock
              Option Plan as of August 22, 2000. (16)*

   10.21      Limited Waiver letter Agreement to Revolving Credit and Term Loan
              Agreement dated as of September 21, 2001.***

   10.22      Agreement with Management & Report Technologies, Inc. (18)

   22.1       Subsidiaries of Registrant.***

   23.1       Consent of Deloitte & Touche, LLP.**

   99.1       Partnership Agreement dated as of July 27, 2000 of CFK Partners by
              and among Philip J. Fagan, M.D., Frederick H. Kopko, Jr. and
              Joseph A. Czyzyk. (13)
</TABLE>

----------

      * Denotes managements contract or compensation plan or arrangement.

        (1)     Such document was previously filed as Appendix A to the
                Company's Proxy Statement for the December 10, 1993 Annual
                Meeting of Shareholders and is incorporated herein by reference.

        (2)     All such documents were previously filed as Exhibits to the
                Company's Quarterly Report on Form 10-Q for the quarter ended
                March 31, 1998 and are incorporated herein by reference.

        (3)     All such documents were previously filed as Exhibits to the
                Company's Registration Statement No. 33-39044 on Form S-2 and
                are incorporated herein by reference.

        (4)     Such document was previously filed as Appendix A to the
                Company's Proxy Statement for the December 2, 1992 Annual
                Meeting of Shareholders.

        (5)     All such documents were previously filed as Exhibits to the
                Company's Registration Statement No. 33-65085 on Form S-1 and
                are incorporated herein by reference.

        (6)     All such documents were previously filed as Exhibits to the
                Company's Quarterly Report on Form 10-Q for the quarter ended
                March 31, 1996 and are incorporated herein by reference.

        (7)     All such documents were previously filed as Exhibits to the
                Company's Report on Form 8-K filed September 13, 1996 and are
                incorporated herein by reference.

        (8)     Such document was previously filed as an Exhibit to the
                Company's Annual Report on Form 10-K for the year ended June 30,
                1997 and is incorporated herein by reference.

        (9)     All such documents were previously filed as an Exhibit to the
                Company's Annual Report on Form 10-K for the year ended June 30,
                1998 and is incorporated herein by reference.

        (10)    Such document was previously filed as Appendix A to the
                Company's Proxy Statement for the December 3, 1998 Annual
                Meeting of Shareholders and incorporated herein by reference.

        (11)    All such documents were previously filed as an Exhibit to the
                Company's Quarterly Report on Form 10-Q for the quarter ended
                March 31, 1999 and incorporated herein by reference.

        (12)    All such documents were previously filed as an Exhibit to the
                Company's Annual Report on Form 10-K for the year ended June 30,
                1999 and is incorporated herein by reference.



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<PAGE>   5

        (13)    Such document was previously filed as an Exhibit to the
                Company's current Report on Form 8-K on August 11, 2000 and is
                incorporated herein by reference.

        (14)    All such documents were previously filed as an Exhibit to the
                Company's Annual Report on Form 10-K for the year ended June 30,
                2000 and is incorporated herein by reference.

        (15)    All such documents were previously filed as an Exhibit to the
                Company's Quarterly Report on Form 10-Q for the quarter ended
                September 30, 2000 and incorporated herein by reference.

        (16)    All such documents were previously filed as an Exhibit to the
                Company's Quarterly Report on Form 10-Q for the quarter ended
                December 31, 2001 and incorporated herein by reference.

        (17)    All such documents were previously filed as an Exhibit to the
                Company's Quarterly Report on Form 10-Q for the quarter ended
                March 31, 2001 and incorporated herein by reference.

        (18)    Such document was previously filed as an Exhibit to the
                Company's Amendment No. 2 in Registration Statement No.
                33-60992 on Form S-1 and is incorporated herein by reference.



    (b) Reports on Form 8-K:

        None



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<PAGE>   6

                                   SIGNATURES

        Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Company has duly caused this Report to be signed on
its behalf by the undersigned thereunto duly authorized in the City of Los
Angeles, State of California, on October 5, 2001.


                                       MERCURY AIR GROUP, INC.


                                       By: /s/ Philip J. Fagan, Jr., M.D.
                                           ------------------------------------
                                           Philip J. Fagan, Jr., M.D.
                                           Chairman of the Board

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed by the following persons in the capacities and on
the dates indicated:

Signers:

Chairman of the Board


<TABLE>
<S>                                                     <C>
/s/ Philip J. Fagan, Jr. M.D.
----------------------------------------
Philip J. Fagan, Jr., M.D.                               Dated: October 5, 2001
Chairman of the Board


Principal Executive Officer and Director:


/s/ Joseph Czyzyk
----------------------------------------
Joseph Czyzyk                                            Dated: October 5, 2001
Chief Executive Officer and Director


Principal Financial and Accounting Officer:


/s/ Randolph E. Ajer
----------------------------------------
Randolph E. Ajer                                         Dated: October 5, 2001
Executive Vice President and Treasurer


Additional Directors:


/s/ Frederick H. Kopko, Jr.
----------------------------------------
Frederick H. Kopko, Jr.                                  Dated: October 5, 2001
Director

/s/ Robert L. List
----------------------------------------
Robert L. List                                           Dated: October 5, 2001
Director

/s/ Harold Bowling
----------------------------------------
Harold Bowling                                           Dated: October 5, 2001
Director
</TABLE>



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