The Brazilian, who has a fractured metatarsal, will miss the Ligue 1 side's last 16 tie against Manchester United, although he could be fit for a potential quarter-final in April.
The first leg against United is scheduled for Old Trafford on Feb. 12 with the return in Paris on March 6.
PSG said in a statement that the 26-year-old Neymar, who left the field in tears after suffering the injury in a French Cup game against Strasbourg on Jan. 23, will not have surgery after the club consulted "world renowned experts" on Tuesday.
"After detailed analysis by the specialists, a consensus was reached of a conservative treatment of Neymar Jr’s injury to the fifth right metatarsal," the statement from the French champions read.
"Informed of this recommendation, Paris Saint-Germain’s Brazilian international striker agreed with this protocol. As a result, Neymar Jr is expected to return to the field within 10 weeks.
"Paris Saint-Germain sends its strongest support and encouragement to Neymar Jr to overcome this injury, with the courage and determination that the player has always shown."
Last year, Neymar was out for 11 weeks after suffering a metatarsal injury on the same right foot, missing PSG's Champions League last-16 exit to holders Real Madrid.
PSG have been marching towards the Ligue 1 title as they lead the standings with 56 points from 20 games, 13 points ahead of second-placed Lille who have played two more games.
Neymar has already suffered groin problems this season but still managed to score 13 goals in the league in as many appearances, adding five in the Champions League.
(Reporting by Julien Pretot; Editing by Ken Ferris)
