The 2004 U.S. Women's Open was the 59th U.S. Women's Open, held July 1–4 at the Orchards Golf Club in South Hadley, Massachusetts, a suburb north of Springfield.

Meg Mallon won her second U.S. Women's Open title, two strokes ahead of runner-up Annika Sörenstam.

The 54-hole leader was Jennifer Rosales at 206 (−7), with Mallon, Sörenstam, and Kelly Robbins three strokes back at 209 (−4).

[2][3] In the final round, Mallon shot 65 (−6) to Sorenstam's 67 (−4), and Rosales fell down to fourth with a 75 (+4).

It was Mallon's fourth and final major title; her first was thirteen years earlier in 1991, also at the U.S.