The Houston Texans pass-rusher had arthroscopic surgery on his left knee after the season, NFL Network's James Palmer reported Thursday.
The Houston Chronicle's John McClain first reported the news.
Palmer noted that Clowney is fine after surgery.
The surgery is minor, but notable due to Clowney's injury history. As a rookie, he had microfracture on his right knee.
Injuries curtailed Clowney's production his first two seasons. He made the leap in 2016, becoming a dominant force after moving from outside linebacker to a defensive end focus.