The 1990 Virginia Slims of Oklahoma was a women's tennis tournament played on indoor hard courts at The Greens Country Club in Oklahoma City, Oklahoma in the United States and was part of the Tier IV category of the 1990 WTA Tour. It was the fifth edition of the tournament and ran from February 19 through February 25, 1990. Third-seeded Amy Frazier won the singles title and earned $27,000 first-prize money.[1]