Australia's ninth seed Samantha Stosur survived a late fightback from unseeded German Angelique Kerber to win their US Open semifinal 6-3, 2-6, 6-2 on Saturday night.

Stosur, one of the most powerful hitters in the women's draw, regained her composure after dropping the second set and failing to serve out the match at her first attempt to become the first Australian to reach the US Open women's final since Wendy Turnbull in 1977, seven years before Stosur was born.

Stosur, who made the final at the French Open last year but lost to Italy's Francesca Schiavone, is bidding to become the first Australian woman to win a grand slam since Evonne Goolagong-Cawley at Wimbledon in 1980.

"This was my third Grand Slam semifinal. I feel there has been some obstacles to get through this tournament, and to come through the way I have, I'm really proud of myself for that," said Stosur.

"And now to be in the final and, I guess getting through those first couple of third and fourth rounds where they were pretty tough matches and I guess having a few days off with rain and now physically feel fine again.

"So I guess that's a good thing. But to get through all those things along the way is definitely very pleasing."

The 27-year-old Queenslander will play the winner of Saturday's second semi between Serena Williams and world No. 1 Caroline Wozniacki in Sunday's final.