EXHIBIT 99.906.CERT.

CERTIFICATIONS PURSUANT TO SECTION 906

OF THE SARBANES-OXLEY ACT

John T. Genoy, President, and Gregory R. Kingston, Treasurer of SunAmerica Series Trust (the “registrant”), each certify to the best of his 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: April 9, 2018

/s/    John T. Genoy        

John T. Genoy

President

/s/    Gregory R. Kingston      

Gregory R. Kingston  

Treasurer