The 1991 Virginia Slims of Philadelphia was a women's tennis tournament played on indoor carpet courts at the Philadelphia Civic Center in Philadelphia, Pennsylvania in the United States that was part of the Tier II category of the 1991 WTA Tour.

It was the ninth edition of the tournament and was held from November 11 through November 17, 1991.

First-seeded Monica Seles won the singles title and earned $70,000 first-prize money.

[1][2] Monica Seles defeated Jennifer Capriati 7–5, 6–1 Jana Novotná / Larisa Savchenko defeated Mary Joe Fernández / Zina Garrison 6–2, 6–4