EXHIBIT 31.1

                                 CERTIFICATIONS

I, Michael A. McManus, Jr., certify that:

I have reviewed this quarterly report on Form 10-Q/A of MISONIX, INC.;

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;

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;

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)) [*** Omitted pursuant to extended
compliance  period]  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)  [***  Omitted  pursuant  to  extended  compliance  period];

     (c)  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

     (d)  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

The  registrant's other certifying officer(s) 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:  September 18, 2003

/s/  Michael A. McManus, Jr.
Michael A. McManus, Jr.
Chief Executive Officer


<PAGE>