The top seed looks determined to go all the way this year, as she powered past Kvitová in straight sets, 7-6(6) 6-2.
After surviving against Alison Riske in the previous round, the Aussie was able to survive an early onslaught by Kvitová in the first set. Saving 8 break points, Barty overcame a temporary lapse in form to claim the first set in a thrilling tiebreak.
Kvitová seemed exhausted at the start of the second set, dropping serve twice to fall to a 0-3 deficit. Perhaps her fourth round victory over Maria Sakkari had taken it's toll, but the Czech was unable to keep up with Barty.
Although the former Wimbledon champion was able to break back and keep the score close at 2-4, another break of serve sealed her fate.
Barty served for the match, saving two break points before claiming this encounter with an ace in an hour and 46 minutes.
The quest for another Major title continues as she takes on American Sofia Kenin, who defeated Ons Jabeur in the other quarterfinal match.