EXHIBIT 32.1

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,

                       AS ADOPTED PURSUANT TO SECTION 906
                        OF THE SARBANES-OXLEY ACT OF 2002

      In  connection  with  the  Quarterly  Report  of  Perma-Fix  Environmental
Services,  Inc.  ("PESI") on Form 10-Q for the  quarter  ended March 31, 2005 as
filed with the Securities and Exchange  Commission on the date hereof (the "Form
10-Q"),  I Dr.  Louis F.  Centofanti,  Chief  Executive  Officer of the Company,
certify,  pursuant to 18 U.S.C.  ss.1350,  as adopted  pursuant to ss.906 of the
Sarbanes-Oxley Act of 2002, that:

     (1) The Form 10-Q fully complies with the  requirements of Section 13(a) or
     15(d)  of the  Securities  Exchange  Act  of  1934  (15  U.S.C.  ss.78m  or
     ss.78o(d)); and

     (2) The  information  contained  in the Form 10-Q fairly  presents,  in all
     material respects, the financial condition and results of operations of the
     Company.

Dated: May 9, 2005


/s/ Louis F. Centofanti
- --------------------------
Dr. Louis F. Centofanti
President and
Chief Executive Officer

This certification is furnished to the Securities and Exchange Commission solely
for purpose of 18 U.S.C.  ss.1350  subject to the knowledge  standard  contained
therein, and not for any other purpose.