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                                                                      EXHIBIT 31

                                 CERTIFICATIONS

I, Paul J. Tufano, certify that:

        1. I have reviewed this quarterly report on Form 10-Q of Maxtor
    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
    registrant as of, and for, the periods presented in this report;

        4. I am responsible for establishing and maintaining disclosure controls
    and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e))
    for the registrant and have:

           (a) Designed such disclosure controls and procedures, or caused such
       disclosure controls and procedures to be designed under my supervision,
       to ensure that material information relating to the registrant, including
       its consolidated subsidiaries, is made known to me by others within those
       entities, particularly during the period in which this report is being
       prepared;

           (b) Evaluated the effectiveness of the registrant's disclosure
       controls and procedures and presented in this report my 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

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

        5. I have disclosed, based on my most recent evaluation of internal
    control over financial reporting, to the registrant's auditors and the audit
    committee of the registrant'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 registrant'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 registrant's internal
       control over financial reporting.

                                                      /s/ Paul J. Tufano
                                                      --------------------------
                                                      Paul J. Tufano
                                                      President, Chief Executive
                                                      Officer and Acting Chief
                                                      Financial Officer

Date: November 4, 2004