In the other semifinals, World No. 2 Victoria Azarenka defeated Flavia Pennetta of Italy 6-4, 6-2, reaching her second straight US Open final.
Both World No. 1 and 2 will go on to the trophy decider of the 2013 US Open tennis tournament.
Williams, who defeated Azarenka in last year's US Open final, will try to capture her 21st career Grand Slam title and fifth US Open crown on Sunday at the Arthur Ashe Stadium, New York.
"She's a great player and she lifts her game when it count," says Williams.
"I'm excited to be in another final and we always have really good matches. I look forward to it. She's a great player and she lifts her game when it counts. I think that's what makes the difference," Sarena Williams said.
In women's doubles semifinals the tenth seed Indo-Chinese pair Sania-Zheng lost to the World No. 8 Ashleigh Barty and Casey Dellacqua of Australia 2-6, 2-6.
Meawhile, India's tennis ace Leander Paes and his Czech partner Radek Stepanek will take on World No. 2 Alexander Peya of Austria and Brazil's Bruno Soares in the US Open men's doubles final.