Czech 19-year-old Vondrousova took a while to get going on Court Philippe-Chatrier and was unable to stop Barty surging to a comprehensive 6-1 6-3 victory.
The teenager has won more matches than any player on the WTA Tour since the Australian Open but acknowledged she was not up to scratch against the newly-crowned champion.
"I think she was just too good. I think she played an amazing match. I didn't have too many chances. I think she just gave me a lesson today," Vondrousova said.
"I didn't really feel good because she didn't let me play my game, and it was really tough."
The unseeded Vondrousova had never advanced beyond the fourth round of a grand slam prior to her run at Roland Garros, which she believes will prove to be life-changing.
"I can't really believe it still because it's a huge thing for me. I think it's going to change my life now," she said.
"But I'm just trying not to think about this and just trying to focus on myself.
"It was an amazing two weeks for me, and I'm just really happy also with the day, even though I lost. But I had my mum and dad here to watch me, so it was kind of nice to have them here.
"It's going to be strange, because I'm going to be seeded at grand slams. A lot of things are going to change now, but I just can't wait to get back home and see what's going to happen."