Australia's Minjee Lee won the 77th US Women's Open on Sunday, rolling to a four-stroke victory to capture her second career major golf title in record-smashing fashion.

The 26-year-old from Perth fired a level par 71 in the final round at Pine Needles in Southern Pines, North Carolina, to finish on a 72-hole event record 13-under 271.

"I'm speechless. I can't believe it right now," Lee said. "It's super special. It has been my dream since I was a little girl. It's the one I've always wanted to win so I'm really happy."

World number four Lee, who took her first major title at last year's Evian Championship, followed in the footsteps of Aussie mentor Karrie Webb, who won a US Women's Open title at Pine Needles in 2001.

The old US Women's Open low 72-hole mark was 272 set by Sweden's Annika Sorenstam at Pine Needles in 1996 and matched by American Juli Inkster in 1999 and South Korean Chun In-gee in 2015.

Lee captured her eighth LPGA title by holding off American Mina Harigae, second on 275 after a closing 72, and claimed a record US$1.8 million top prize from a US$10-million purse, the richest in women's golf history.

"We're only moving in the right direction," Lee said of the prize money. "It's only going to get better from here. It's such a large sum. I'm honored to be the first winner of the sum but it's only going to get better and better."

South Korean Choi Hye-jin was third on 277, one stroke ahead of world number one Ko Jin-young of South Korea with New Zealand's Lydia Ko fifth on 279.

Lee began with a three-stroke lead over Harigae and a six-shot edge on the rest of the field, with the best final-round comeback by a US Women's Open winner being five strokes.

Lee opened with back-to-back birdies to reach 15-under, a 35-foot birdie putt at the second hole stretching her lead to five shots, but she found a greenside bunker and made bogey at the par-3 fifth.

At the seventh, Lee's tee shot went next to a weed in the sandy native area. She blasted out to greenside fringe but took a bogey, yet kept her four-stroke lead when Harigae made bogey as well.

Lee sank a clutch seven-foot par putt at the ninth and made another par save at the par-5 10th, where her second shot bounced over the green and landed in a dead bush. Lee wedged a bump-and-run shot to the far side of the green and two-putted.

Harigae, who settled for her first top-10 major finish, made a bogey at 11 and Lee sank an eight-foot birdie putt at the 12th, then birdied the par-5 15th to keep a six-stroke edge.

That was plenty for Lee to grab the triumph despite a bogey at the par-3 16th and a tap-in miss to bogey the 18th. (AFP)