Exhibit 32.1

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

         In connection with the Quarterly Report of USG Corporation (the
"Corporation") on Form 10-Q for the quarter ended June 30, 2003, as filed with
the Securities and Exchange Commission on the date hereof (the "Report"), I,
William C. Foote, Chairman, Chief Executive Officer and President of the
Corporation, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002, that to the best of my knowledge:

(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.

August 5, 2003                   /s/ William C. Foote
                                 -----------------------------------------------
                                 William C. Foote
                                 Chairman, Chief Executive Officer and President

A signed original of this written statement required by Section 906 has been
provided to USG Corporation and will be retained by USG Corporation and
furnished to the Securities and Exchange Commission or its staff upon request.