The top seed beat Croatia's Petra Martic 6-3 6-2, and will face either Shahar Peer or Alexandra Cadantu in the last four.
Italian world number 13 Roberta Vinci also made the semis with the simplest of wins over Karolina Pliskova.
Vinci, who came through a tough second round battle against Kiki Bertens, blitzed Pliskova in a 6-1 6-0 win to set up a match against Annika Beck.
WTA Katowice quarter-final results:
1-Petra Kvitova (Czech Republic) beat Petra Martic (Croatia) 6-3 6-2
Annika Beck (Germany) beat Maria Elena Camerin (Italy) 7-6(1) 6-0
2-Roberta Vinci (Italy) beat Karolina Pliskova (Czech Republic) 6-1 6-0
- Sports & Recreation
- Roberta Vinci
- Petra Martic
- Alexandra Cadantu