The 2011 champion Petra Kvitova will face fellow Czech and first-time Grand Slam semi-finalist Lucie Safarova in the last four at Wimbledon.
Kvitova, the sixth seed, was too strong for another compatriot, Barbora Zahlavova Strycova, winning 6-1 7-5.
Zahlavova Strycova knocked out second seed Li Na and 16th seed Caroline Wozniacki in the previous two rounds.
Safarova, who has lost all five previous meetings with Kvitova, beat 22nd seed Ekaterina Makarova 6-3 6-1.
It is the first time two Czech women have advanced to the semi-finals at the same Grand Slam since Hana Mandlikova and Helena Sukova at the 1986 French Open.
Kvitova, whose best Grand Slam form has come at Wimbledon, broke in the opening game of the match, quickly wrapping up the set.
But her compatriot came more into the match in the second set and served for the set at 5-4 only for Kvitova to step up her game and break to level the match.
Kvitova held to go 6-5 up, putting pressure on Strycova to stay in the match. The world number 43 was unable to respond and Kvitova broke serve again to seal victory.
Russian Makarova had caused a shock in the previous round by beating fourth seed Agnieszka Radwanska but was unable to raise her game again against Safarova.
"I played really well and wanted to get through this match and I am so happy," said a delighted Safarova, who was making her 37th Grand Slam appearance.
"I was serving well and being aggressive and taking her time away and that was the key to the victory."
|Two-time Grand Slam champion Tracy Austin on Safarova's win:|
|"The crowd were on their feet afterwards because I think they saw how important that win was to Safarova. To make her first semi-final means the world to her. She puts in a lot of work and has done since she first came on the tour around a decade ago. This is the biggest moment of her career but she handled the situation better and served extremely well and played a great match."|