The 1991 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 that was part of Tier IV of the 1991 WTA Tour. It was the sixth edition of the tournament was held from February 18 through February 24, 1991. First-seeded Jana Novotná won the singles title and earned $27,000 first-prize money.[1][2]