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                                                                    Exhibit 31.2

                                 CERTIFICATIONS

I, Bruce D. Horn, certify that:

1.    I have reviewed this quarterly report on Form 10-Q of Oplink
Communications, 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(s) 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; and

5.    The registrant's other certifying officer(s) and I have disclosed, based
on our most recent evaluation of internal control over financing 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: May 11, 2004

                                             /s/ Bruce D. Horn
                                             -----------------------------------
                                             Bruce D. Horn
                                             Chief Financial Officer
                                             (Principal Financial Officer)