EXHIBIT 32.1

                           SECTION 1350 CERTIFICATIONS

In connection with the Quarterly Report of USG Corporation (the "Corporation")
on Form 10-Q, 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.

May 4, 2004                      /s/ William C. Foote
                                 -----------------------------------------------
                                 William C. Foote
                                 Chairman, Chief Executive Officer and President

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