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                                                                    EXHIBIT 31.1

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

   I, Richard J. Naughton, Chief Executive Officer of Xenonics Holdings, Inc.,
certify that:

      1. I have reviewed this Quarterly Report on Form 10-QSB of Xenonics
Holdings, 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 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: August 12, 2005              /s/ Richard J. Naughton
                                         _______________________________________
                                         Name:  Richard J. Naughton
                                         Title: Chief Executive Officer