The two-time Wimbledon champion was sidelined for five months as she recovered from injuries to her left playing hand suffered while fighting off a knife-wielding burglar at her home in the Czech Republic in December.
Kvitova returned to competitive action at the French Open in May. She won her opening match but lost in the second round.
Though she started the final as favourite, Kvitova was aware of Barty’s prowess. In the semi-final, the unseeded Australian beat the sixth seed Garbine Muguruza.
And the 21-year-old continued in the same vein of form that had destroyed the Spaniard. She lost only one point in her first four service games.
"I think it was a high quality match,” said Barty. “We both started well and I served particularly well in the first set and it gave me the upper hand.”
But that was as good as it got for Barty. Kvitova raced into a 5-1 lead in the second before claiming it 6-3 and it was one way traffic in the decider as the seventh seed completed the victory in one hour and 47 minutes.
“It’s amazing to have Petra back on the court,” said Barty generously after the final. “She’s such an inspiration. She’s always been a great champion but I think we appreciate that more now that she’s back playing week-in and week-out. Hopefully she is able to stay healthy and doesn’t have any more issues.”
Kvitova, who was in tears after her opening round victory at Roland Garros in May, said: "I could not have imagined a comeback better than the one I am having now. The hand is good. This is the best news I could have and I am not feeling any pain and that's the best news."