EXHIBIT 99.2

                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                    AS ADOPTED PURSUANT TO SECTION 906 OF THE
                           SARBANES-OXLEY ACT OF 2002

         Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 and in
connection with the Annual Report on Form 10-K of National Service Industries,
Inc. (the "Corporation") for the fiscal year ended August 31, 2002, as filed
with the Securities and Exchange Commission on the date hereof (the "Report"),
the undersigned, the Senior Vice President, Chief Financial Officer and
Treasurer certifies that:

         (1) The Report fully complies with the requirements of Section 13(a) or
15(d) of the Securities Exchange Act of 1934; and

         (2) The information contained in the Report fairly presents, in all
material respects, the financial condition and results of operations of the
Corporation.

/s/ Chester J. Popkowski
- --------------------------------------
Chester J. Popkowski
Senior Vice President, Chief Financial
Officer and Treasurer
November 15, 2002