Melbourne amateur Keeley Marx is set to make her major championship debut after joining at least four other Australians in qualifying for the US Women's Open later this month.

Marx, 20, won the USGA's qualifying event at Briarwood Country Club near Chicago on Monday by a shot with scores of 69-72. The Heritage member was one of just two players to qualify from that tournament.

Marx, 20, is on a scholarship at Iowa State University having carved a fine amateur career at home, including an IMG World Junior Championship in 2022 and representing Australia at an Asia-Pacific Championship.

The Victorian joins Minjee Lee, Hannah Green, Gabriela Ruffels and Steph Kyriacou in the field.

She is one of three Australians to win qualifying events for the richest tournament in women's golf. Ruffels (San Joaquin Country Club) and Kyriacou (Sugar Mill Country Club) also were medallists at qualifiers over the past few weeks.

The US Women's Open is at Lancaster Country Club in Pennsylvania from May 30 to June 2.

The prize pool is at a record $US12 million this year.