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EXHIBIT 31.1

                           APPLIED DNA SCIENCES, INC.
                  OFFICER'S CERTIFICATE PURSUANT TO SECTION 302

I, James A. Hayward, certify that:

    1.            I have reviewed this amended quarterly report on Form 10-QSB/A
                  of Applied DNA Sciences, Inc.;

    2.            Based on my knowledge,  this quarterly 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
                  quarterly report;

    3.            Based on my  knowledge,  the financial  statements,  and other
                  financial  information  included  in  this  quarterly  report,
                  fairly   present  in  all  material   respects  the  financial
                  condition,  results of operations  and cash flows of the Small
                  Business Issuer as of, and for, the periods  presented in this
                  quarterly report;

    4.            The Small Business  Issuer's other  certifying  officers 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))  and internal  control over financial
                  reporting  (as defined in  Exchange  Act Rules  13a-15(f)  and
                  15d-15(f)) for the Small Business Issuer 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  small  business  issuer,
                         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)   [Omitted pursuant to SEC Release No. 33-8238];

                   (c)   Evaluated    the  effectiveness  of the Small  Business
                         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

                   (d)   Disclosed    in  this  report  any  change in the Small
                         Business   Issuer's  internal  control  over  financial
                         reporting that occurred during   the   small   business
                         issuer's most recent fiscal quarter (the small business
                         issuer's fourth fiscal quarter in the case of an annual
                         report) that has materially affected, or  is reasonably
                         likely to materially affect,the small business issuer's
                         internal control over financial reporting; and

    5.            The Small Business Issuer's other certifying  officer(s) and I
                  have  disclosed,  based  on  our  most  recent  evaluation  of
                  internal  control  over  financial  reporting,  to  the  small
                  business  issuer's  auditors  of the small  business  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 small business 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 small   business  issuer's internal control
                         over financial reporting.




Date:  February 29, 2008


/s/  JAMES A. HAYWARD
---------------------
James A. Hayward
Chief Executive Officer