Sharapova, ranked No. 2 in the world, had little trouble in dispatching 23rd-seeded Kaia Kanepi 6-2, 6-3. Kvitova, seeded fourth, won the last four games of the last two sets in a 3-6, 6-2, 6-4 decision over qualifier Yaroslava Shvedova.
Sharapova owns a 3-2 series edge after taking the last two matches against Kvitova. Kvitova, however, defeated Sharapova in the finals at Wimbledon last year.
The other semifinal Thursday pits sixth-seeded Samantha Stosur against No. 21 Sara Errani. Stosur is 5-0 lifetime versus Errani. Both won quarterfinal matches in straight sets Tuesday.
Thursday's winners play for the French Open women's singles title Saturday. None of the semifinalists has previously won the French Open.
Sharapova, who needs the French Open title for the career Grand Slam, has lost just one set in her run to the semis. Wednesday she had seven breaks in nine receiving games and won 58 percent of the points off Kanepi's serve.
Kvitova was down a set and a break at one point and 2-4 in third set before righting her game. She had 38 winners -- to 14 for Shvedova -- but also 32 unforced errors. She countered five Shvedova service breaks with seven breaks of her own, with three each in the final two sets.