Exhibit 31.2

           CHIEF FINANCIAL OFFICER CERTIFICATION PURSUANT TO 18 U.S.C.
                SECTION 1350, AS ADOPTED PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002

I, John Ornell, the Chief Financial Officer of Waters Corporation, certify that:

1.    I have reviewed this quarterly report on Form 10-Q of Waters 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.    The registrant's other certifying officer(s) and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15e and 15d-15e) and internal control
      over financial reporting (as defined in Exchange Act Rules 13a-15(f) and
      15d-15(f)) 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)    designed such internal control over financial reporting, or
                 caused such internal control over financial reporting to be
                 designed under our supervision, to provide reasonable assurance
                 regarding the reliability of financial reporting and the
                 preparation of financial statements for external purposes in
                 accordance with generally accepted accounting principles;

           c)    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

           d)    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(s) 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
      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: May 6, 2005

                                                 /s/ John Ornell
                                                 -------------------
                                                 John Ornell
                                                 Chief Financial Officer