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                                                             Exhibit 99.906.Cert

                    CERTIFICATIONS PURSUANT TO SECTION 906
                          OF THE SARBANES-OXLEY ACT

Robert M. Zakem, President, and Donna M. Handel, Treasurer of SunAmerica
Strategic Investment Series, Inc. (the "Registrant"), each certify to the best
of his or her knowledge that:

1. The attached Form N-CSR report of the Registrant fully complies with the
   requirements of Sections 13(a) and 15(d) of the Securities Exchange Act of
   1934; and

2. The information contained in such N-CSR report fairly represents, in all
   material respects, the financial conditions and results of operations of the
   Registrant as of, and for, the periods presented in the report.

Dated: December 17, 2003

/s/ Robert M. Zakem
Robert M. Zakem
President

/s/ Donna M. Handel
Donna M. Handel
Treasurer

A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature that
appears in typed form within the electronic version of this written statement
required by Section 906, has been provided to the Registrant and will be
retained by the Registrant and furnished to the Securities and Exchange
Commission or its staff upon request.