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                                                                    Exhibit 31.2

                             MERCURY AIR GROUP, INC

                           CERTIFICATIONS PURSUANT TO
                                 SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

CERTIFICATION

I, Robert Schlax, certify that:

            1. I have reviewed this quarterly report on SEC Form 10-Q of Mercury
      Air Group, Inc.;

            2. Based on my knowledge, this report does not contain any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements made, in light of the circumstances under which such
      statements were made, nor misleading with respect to the period covered by
      this report;

            3. Based on my knowledge, the financial statements, and other
      financial information included in this report, fairly present in all
      material respects the financial condition, results of operations and cash
      flows of the registrant as of, and for, the periods presented in this
      report;

            4. The registrant's other certifying officer and I are responsible
      for establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant
      and have;

            a. designed such disclosure controls and procedures, or caused such
      disclosure controls and procedures to be designed under our supervision,
      to ensure that material information relating to the registrant including
      its consolidated subsidiaries, is made known to us by others within those
      entities, particularly during the period in which this report is being
      prepared;

            b. evaluated the effectiveness of the registrant's disclosure
      controls and procedures and presented in this report our conclusions about
      the effectiveness of the disclosure controls and procedures as of the end
      of the period covered by this report based on such evaluation; and

            c. disclosed in this report any changes in the registrant's internal
      control over financial reporting that occurred during the registrant's
      most recent fiscal quarter that has materially affected, or is reasonably
      likely to materially affect, the registrant's internal controls over
      financial reporting; and

            5. The registrant's other certifying officer and I have disclosed,
      based on our most recent evaluation of internal controls over financial
      reporting, to the registrant's auditors and the audit committee of
      registrant's board of directors (or persons performing similar functions);

            a. all significant deficiencies and material weaknesses in the
      design or operation of internal controls over financial reporting which
      are reasonably likely to adversely affect the registrant's ability to
      record, process, summarize and report financial information; and

            b. any fraud, whether or not material, that involves management or
      other employees who have a significant role in the registrant's internal
      controls over financial reporting.

                                         /s/ Robert Schlax
                                         --------------------------------------
                                         Robert Schlax
                                         Chief Financial Officer

February 17, 2004