With his Czech opponent leading 4-3 in the first set, Sharapova sprained left ankle before serving in the eighth Thurs limped to his chair and went out after talking with his coach.
It was a rematch of this year's Wimbledon final, where Kvitova beat Sharapova 6-3, 6-4 for his first major title.
Kvitova face now the fourth of Russia Vera Zvonareva, who beat compatriot Maria Kirilenko 6-3, 6-3 in another quarterfinal.
Zvonareva had five aces in the match, which lasted 1 hour, 14 minutes Ariake Colosseum, and rose to 6-0 head to head matches against top-seeded Kirilenko.
"I am very pleased that my department has helped me today,''Zvonareva said." The first service was good and my second serve, even caused him some problems, and has made a big difference.''
KO Kirilenko Open champion United States beat Samantha Stosur and Tuesday 12-seeded Ana Ivanovic on Wednesday, but struggled with his serve against Zvonareva, breaking three times.
"Maria is a great player and a great fighter and he proved by beating two tough opponents on his way to the quarterfinals,''said Zvonareva." There is no secret to beating her. I just tried to take some pictures which caused him some discomfort and was able to do.''
In addition, third-seeded Victoria Azarenka of Belarus beat seventh-seeded Marion Bartoli, France 7-5, 6-0 to reach the final four. Next faces either Estonia or Poland's Agnieszka Radwanska Kaia Kanepi, who play later Thursday
