Hannah Green broke through for her first major title by winning the Women's PGA Championship.

Green carded a final-round 72 to complete a wire-to-wire one-stroke victory at Hazeltine National Golf Club on Sunday.

The 22-year-old mixed three birdies with three bogeys as she became the first Australian since Hall of Famer Karrie Webb in 2001 to win the LPGA Tour tournament.

A five-foot par on the final hole saw Green finish nine under overall, just ahead of defending champion Park Sung-hyun (68), who birdied the 18th before her unheralded rival made a clutch putt.

"I'm pretty much speechless," a tearful Green said. "I was really nervous the last five holes and just really – I made a clutch putt and that was what kind of got me through another one. To make the one on the last is really surreal."

"It's awesome," added Green. "I've always wanted to win in front of an Aussie crowd. I felt even that's what it was like today. Anything to just be winning in majors the first event. 

"I actually didn't feel too nervous the first few. Obviously I heard Sung made the last one, knew I needed to make par. Didn't want to play that hole again. I'm really happy I made it."

Englishwoman Mel Reid posted a six-under-par 66 to earn a share of third position alongside American Nelly Korda (71) at six under.

Meanwhile, American pair Danielle Kang (70) and Lizette Salas (72) rounded out the top five – four shots behind Green.