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                                                                   EXHIBIT 31.2

                             NOVELLUS SYSTEMS, INC.

                                 CERTIFICATION

   I, Kevin S. Royal, certify that:

1. I have reviewed this annual report on Form 10-K of Novellus Systems, Inc.;

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. 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 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.

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.

    Dated:  March 12, 2004            By: /s/ Kevin S. Royal
                                         ---------------------------------------
                                      Kevin S. Royal
                                      Vice President and Chief Financial Officer