EXHIBIT 32.2

                           SECTION 1350 CERTIFICATIONS

In connection with the Annual Report of USG Corporation (the "Corporation") on
Form 10-K, as filed with the Securities and Exchange Commission on the date
hereof (the "Report"), I, Richard H. Fleming, Executive Vice President and Chief
Financial Officer 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.

February 24, 2004                            /s/ Richard H. Fleming
                                             ---------------------------------
                                             Richard H. Fleming
                                             Executive Vice President and
                                             Chief Financial Officer

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