Tracy Austin defeated Martina Navratilova in the final, 1–6, 7–6(7–4), 7–6(7–1) to win the women's singles tennis title at the 1981 US Open.

Chris Evert was the defending champion, but lost in the semifinals to Navratilova.

The loss ended Evert's streak of six consecutive US Open finals.

Tracy Austin is the champion; others show the round in which they were eliminated.

This edition of the US Open was the first time that the women's singles tournament featured a 128-player draw.