The 1991 U.S. Women's Open was the 46th edition of the U.S. Women's Open, held July 11–14 at Colonial Country Club in Fort Worth, Texas. Meg Mallon shot a final round 67 (−4) to finish at 283 (−1), two strokes ahead of runner-up Pat Bradley. Mallon trailed Bradley by three strokes with ten holes to play. It was the second of Mallon's four major titles; she won the LPGA Championship two weeks earlier. Mallon won her second U.S. Women's Open and final major thirteen years later in 2004.