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                                                                    EXHIBIT 31.2

CERTIFICATION OF THE CHIEF FINANCIAL OFFICER PURSUANT TO SECTION 302 OF THE OF
THE SARBANES-OXLEY ACT.

I, Donna G. Lee, Chief Financial Officer of Xenonics Holdings, Inc. certify
that:

     1.   I have reviewed this report on Form 10-KSB of Xenonics Holdings, Inc.;

     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 periods 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 issuer's other certifying officer and I are responsible for
          establishing and maintaining disclosure controls and procedures (as
          defined in Exchange Act Rules 13a-14 and 15d-14) 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 issuer'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 issuer's internal
                    control over financial reporting that occurred during the
                    issuer's most recent fiscal quarter that has materially
                    affected, or is reasonably likely to materially affect, the
                    issuer's internal control over financial reporting; and

     5.   The issuer's other certifying officer and I have disclosed, based on
          our most recent evaluation, to the issuer's auditors and the audit
          committee of issuer'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 issuer'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
                    issuer's internal control over financial reporting.

Date: December 21, 2004                                 /s/  Donna G. Lee
                                                  ------------------------------
                                                  Name:  Donna G. Lee
                                                  Title: Chief Financial Officer