| 1991 Virginia Slims of Chicago | |
|---|---|
| Date | February 11–17 |
| Edition | 20th |
| Category | Tier II |
| Draw | 28S / 14D |
| Prize money | $350,000 |
| Surface | Carpet (Supreme) / indoor |
| Location | Chicago, Illinois, U.S. |
| Venue | UIC Pavilion |
| Champions | |
| Singles | |
 Martina Navratilova | |
| Doubles | |
Gigi Fernández  Jana Novotná | |
The 1991 Virginia Slims of Chicago was a women's tennis tournament played on indoor carpet courts at the UIC Pavilion in Chicago, Illinois in the United States and was part of the Tier II category of the 1991 WTA Tour. It was the 20th edition of the tournament and was held from February 11 through February 17, 1991. First-seeded Martina Navratilova won the singles title, her 11th at the event and earned $70,000 first-prize money as well as 300 ranking points. [1]