After a sluggish start with both players dropping serve, Russian-born Rybakina raised her level and cruised through the first set.
In the second set, Svitolina was no match again for Rybakina as the 19th-ranked Ukrainian showed signs of fatigue from the start and lacked precision under the long-awaited sun after a wet first week on the Paris red clay.
The Kazakh said she would need to be more consistent when she plays 15th-ranked Italian Jasmine Paolini who has reached the last eight for the first time after beating Elina Avanesyan 4-6, 6-0, 6-1.
"It's all about focus now, the matches are getting tougher, the opening also, so I think it's a lot about the consistency, not having so many ups and downs," she said.
Svitolina had reached the quarter-finals four times before, including 2023, but was unable to trouble the former Wimbledon champion.
"I missed my chance, but she's a great player. It's always tricky because you feel like you're so close, but at the same time so far," Svitolina said.
Rybakina withdrew from the French Open last year before her third-round match because of illness.
This season, after winning titles in Brisbane, Abu Dhabi and Stuttgart, Rybakina pulled out of the Italian Open due to health issues.
Rybakina is the only player to beat Iga Swiatek on clay this year, defeating the world number one and three-times French Open champion on her way to the Stuttgart title in April.
