Cavani had to be replaced in the 75th minute of PSG's 2-0 home victory over Girondins Bordeaux in Ligue 1 on Friday and underwent further examination the following day.
A club spokesman told Reuters that the Uruguay striker would be out of action for at least three weeks.
The 26-year-old Cavani has scored 20 goals in 30 matches in all competitions since joining the Ligue 1 leaders from Napoli for a French record fee of 64 million euros (£52 million) this season.
He will miss PSG's League Cup semi-final tie at Nantes on Tuesday, and next weekend's Ligue 1 clash at second-placed Monaco, who are five points behind after 23 games.
PSG visit Leverkusen in a last 16 first-leg match on Feb. 18 before hosting the return on March 12.