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                                                                    Exhibit 31.1

                    CERTIFICATION PURSUANT TO SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

I, Robert E. Lee, President and Chief Executive Officer of Millennium  Chemicals
Inc., certify that:

     1.  I have reviewed the annual report on Form 10-K of Millennium Chemicals
         Inc. as filed with the Securities and Exchange Commission on March 25,
         2003 and as amended by Form 10-K/A filed with the Securities and
         Exchange Commission on the date hereof;

     2.  Based on my knowledge, this annual 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 annual report;

     3.  Based on my knowledge, the financial statements, and other financial
         information included in this annual 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 annual report;

     4.  The registrant'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
         registrant 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
               registrant, including its consolidated subsidiaries, is made
               known to us by others within those entities, particularly during
               the period in which this annual report is being prepared;

            b) evaluated the effectiveness of the registrant'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

            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.  The registrant's other certifying officer and I have disclosed, based
         on our 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.



Date: November 12, 2003


                                              /s/ ROBERT E. LEE
                                  --------------------------------------------
                                                  Robert E. Lee
                                   President and Chief Executive Officer
                                        (Principal Executive Officer)