As filed with the Securities and Exchange Commission on September 9, 2003

                                                     Registration No. 333-106215
  ______________________________________________________________________________


                       SECURITIES AND EXCHANGE COMMISSION
                                WASHINGTON, D.C.

                            -------------------------

                         POST-EFFECTIVE AMENDMENT NO. 1
                                       to
                                    FORM S-3

                             Registration Statement
                                    Under The
                             Securities Act of 1933

                            -------------------------

                           INTERNATIONAL ISOTOPES INC.
                 ----------------------------------------------
                 (Name of Small Business Issuer in its Charter)

               Texas                          2835                 74-276837
 -------------------------------  ----------------------------  ----------------
 (State or other Jurisdiction of  (Primary Standard Industrial  (I.R.S. Employer
  Incorporation or Organization)   Classification Code Number)   Identification
                                                                    Number)

                  4137 Commerce Circle Idaho Falls, Idaho 83401
          ------------------------------------------------------------
          (Address and Telephone Number of Principal Executive Offices
                        and Principal Place of Business)

                                 Steve T. Laflin
                              4137 Commerce Circle
                            Idaho Falls, Idaho 83401
                                 (208) 524-5300
            ---------------------------------------------------------
            (Name, Address and Telephone Number of Agent for Service)

                                    Copy to:
                                Curtis R. Ashmos
                            Locke Liddell & Sapp LLP
                             100 Congress, Suite 300
                               Austin, Texas 78701
                                 (512) 305-4716

                Approximate Date of Proposed Sale to the Public:
     From time to time after this Registration Statement becomes effective.

         If the only securities  being registered on this form are being offered
pursuant to dividend or interest reinvestment plans, check the following box. ||

         If any of the  securities  being  registered  on  this  form  are to be
offered  on a  delayed  or  continuous  basis  pursuant  to Rule 415  under  the
Securities Act of 1933, check the following box. |X|

         If this form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list  the  Securities  Act  registration  statement  number  of the  earlier
effective registration statement for the same offering. ||

         If this  form is a  post-effective  amendment  filed  pursuant  to Rule
462(c) under the Securities Act, check the following box and list the Securities
Act  registration   statement  number  of  the  earlier  effective  registration
statement for the same offering. ||

         If delivery of the  prospectus  is expected to be made pursuant to Rule
434, please check the following box. ||






Item 16. Exhibits.

(a)      Exhibits


         23.1         Consent of Hansen, Barnett & Maxwell.







                      POWER OF ATTORNEY TO SIGN AMENDMENTS

         KNOW  ALL MEN BY THESE  PRESENTS,  that  each  person  whose  signature
appears below does hereby  constitute  and appoint Steve T. Laflin and Dr. Ralph
M. Richart, and each of them, with full power to act without the other, his true
and lawful  attorney-in-fact and agent for him and in his name, place and stead,
in any and all  capacities,  to sign any or all amendments to this  Registration
Statement and to file the same, with all exhibits  thereto,  and other documents
in connection therewith,  with the Securities and Exchange Commission,  granting
unto  said  attorneys-in-fact  and  agents,  and each of them,  full  power  and
authority to do and perform each and every act and thing requisite and necessary
to be done in and about the premises in order to effectuate  the same, as fully,
for all  intents  and  purposes,  as he  might or  could  do in  person,  hereby
ratifying and confirming all that said  attorneys-in-fact  and agents, or any of
them, may lawfully do or cause to be done by virtue hereof.









                                   SIGNATURES


         In accordance  with the  requirements  of the  Securities  Act of 1933,
Registrant certifies that it has reasonable grounds to believe that it meets all
of the  requirements  for filing on Form S-3 and authorized this Amendment No. 1
to the POST-Effective  Registration  Statement to be signed on its behalf by the
undersigned, in Idaho Falls, State of Idaho, on the 9th day of September, 2003.





                                           By: /s/ Steve T. Laflin
                                               -------------------
                                               Steve T. Laflin
                                               President and CEO

         In accordance with the requirements of the Securities Act of 1933, this
Amendment No. 1 to the Post-Effective  Registration Statement has been signed by
the following persons in the capacities and on the dates stated.


  Signature                       Title                        Date

  /s/ Steve T. Laflin             President, CEO and CFO       September 9, 2003
  ------------------------
  Steve T. Laflin

  /s/ Dr. Ralph M. Richart        Chairman                     September 9, 2003
  ------------------------
  Dr. Ralph M. Richart

  /s/ Christopher Grosso          Director                     September 9, 2003
  ------------------------
  Christopher Grosso