EXHIBIT 31.1

                                 CERTIFICATIONS

I, William C. Foote, certify that:

1. I have reviewed this quarterly report on Form 10-Q of USG Corporation;

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, not 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
   Corporation as of, and for, the periods presented in this report;

4. The Corporation'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 Corporation 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
            Corporation, 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;

      (c)   Evaluated the effectiveness of the Corporation'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

      (d)   Disclosed in this report any change in the Corporation's internal
            control over financial reporting that occurred during the
            Corporation's most recent fiscal quarter (the Corporation's fourth
            fiscal quarter in the case of an annual report) that has materially
            affected, or is reasonably likely to materially affect, the
            Corporation's internal control over financial reporting; and

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

      (a)   All significant deficiencies and material weaknesses in the design
            or operation of internal control over financial reporting which are
            reasonably likely to adversely affect the Corporation'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 Corporation's
            internal controls over financial reporting.

November 1, 2004                       /s/ William C. Foote
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                                       William C. Foote
                                       Chairman, Chief Executive Officer and
                                       President

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