PSG - whose starting lineup possessed less experience that Bayern - were holding their own, but Franck Ribery nearly gave the German outfit the lead when firing wide of the post after good hold-up play from Sandro Wagner.
However, PSG went ahead just after the half-hour mark when Timothy Weah was played through on goal and fired past Ulreich after holding off pressure from a defender.
Christopher Nkunku also had an opportunity as the first half progressed towards a close, but the youngster failed to make the most of a chance after creating room for himself.
Bayern had been second best, but Wagner came close to an equaliser just after the restart, with the forward's deflected header striking the crossbar before going out of play.
Nkunku twice had the opportunity to double PSG's advantage before the hour mark but somehow failed to hit the target on both occasions, firstly firing wide from close range and then blazing over from no more than eight yards.
The Bundesliga champions doubled their advantage with 22 minutes left through Renato Sanches, with the Portugal international curling a wonderful free kick into the net with goalkeeper Remy Descamps expecting a cross.
BAYERN MUNICH: Ulreich, Rafinha (Johansson 71'), Bernat (Granbry 62'), Martinez (Richards 62'), Stanisic (Alaba 46'), Sanches (Zylla 70'), Batista Meier (Shabani 46'), Robben (Meier 62'), Will, Ribery (Coman 45'), Wagner (Zirkzee 62')
PARIS SAINT-GERMAIN: Buffon (Descamps 66'), Rimane, Mbe Soh, N'Soki, Dagba (Georgen 84'), Diarra (Zagre 72'), Nkunku (Postolachi 72'), Rabiot (Jese 72'), Toufiqui (Fressange 84'), Bernede, Weah