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                                                                     EXHIBIT 31
                         SALIVA DIAGNOSTIC SYSTEMS, INC.
                                 MARCH 31, 2003


                                 CERTIFICATIONS
                                ----------------

   I, Leo Ehrlich, certify that:

          1.  I have  reviewed  this  quarterly  report on Form 10-QSB of Saliva
              Diagnostic 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.  I am  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.  I have disclosed,  based on my 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:  April 15, 2004

                                       /s/ Leo Ehrlich
                                       -----------------------------------------
                                       Leo Ehrlich
                                       President & Chief Financial Officer