She becomes the first Aussie to win the singles title here since Margaret Court in 1973.
Barty, who was world No.623 when she returned to tennis three years ago after a spell playing the Women’s Big Bash League, is now the world No.2
The final started at 4.31pm local time – 91 minutes later than scheduled – because of the Dominic- Thiem-Novak Djokovic semi-final.
Vondrousova had knocked out Jo Konta in the semi-final yesterday and had not dropped a set all tournament. But on her first ever appearance on the main Court Philipp-Chatrier, the world No.38 started nervously and lost the first four games in 14 minutes. She finally got on the board with her first game after 19 minutes but the first set was over embarrassingly quickly in 30 minutes.
FRENCH OPEN RESULTS – WOMEN’S SINGLES
The No.8 seed broke early again in the second set but Vondrousova finally showed some form and won three games but Barty ended the one-sided final after 70 minutes when she put away a smash.
Barty said: “It was the perfect match. I am so proud of myself and my team. It has been a crazy two weeks. I was very nervous too.
“Marketa has had a fantastic tournament and will be in many more Grand Slam finals.”
Asked about being the first winner here since Court, the Aussie added: “This is a special place for Australian players. Sam Stosur has done well here in the past.
“She has been close. I am very proud. It has been a magical two weeks.”
Martina Navratilova on ITV4 said: “This could be a great springboard for her. I am so glad the sport has got her back.
“She must be one of the favourites for Wimbledon now. She has the slice and great variety in her game.
“I don’t think she is a one-Slam wonder. I think we will see her win again.”