CERTIFICATION PURSUANT TO RULE 30A-2(B) UNDER THE 1940 ACT AND
                     SECTION 906 OF THE SARBANES-OXLEY ACT

I, Bruce N. Alpert, Principal Executive  Officer of GAMCO  International  Growth
Fund, Inc. (the "Registrant"), certify that:

     1.  The Form N-CSR of the Registrant (the "Report") fully complies with the
         requirements  of Section 13(a) or 15(d) of the Securities  Exchange Act
         of 1934, as amended; and

     2.  The  information  contained  in  the  Report  fairly  presents,  in all
         material respects, the financial condition and results of operations of
         the Registrant.


Date:    03/01/2007                 /s/ Bruce N. Alpert
     --------------------           --------------------------------------------
                                    Bruce N. Alpert, Principal Executive Officer



I, Agnes Mullady, Principal Financial Officer & Treasurer of GAMCO International
Growth Fund, Inc. (the "Registrant"), certify that:

     1.  The Form N-CSR of the Registrant (the "Report") fully complies with the
         requirements  of Section 13(a) or 15(d) of the Securities  Exchange Act
         of 1934, as amended; and

     2.  The  information  contained  in  the  Report  fairly  presents,  in all
         material respects, the financial condition and results of operations of
         the Registrant.


Date:    03/01/2007                 /s/ Agnes Mullady
     ---------------------          --------------------------------------------
                                    Agnes Mullady,
                                    Principal Financial Officer & Treasurer