As expected, PSG made wholesale changes with one eye on their crucial second-leg semi-final clash with Arsenal in the UEFA Champions League on Wednesday.
One player to get a chance from the start was Goncalo Ramos, who should have put the visitors ahead after just three minutes when he glanced his header narrowly wide.
That miss proved costly as Strasbourg took the lead when Lucas Hernandez unluckily sliced into his own net from a corner.
Ramos was then denied by Dorde Petrovic from close range, before the hosts grabbed a brilliant second goal in added time at the end of the first half.
Habib Diarra laid off to Felix Lemarechal on the edge of the box, and he curled sweetly into the top corner.
PSG halved the deficit immediately in the second half though, as Bradley Barcola produced some individual magic to dribble his way into the box and coolly slot past Petrovic.
The goalkeeper then had to be alert to parry Fabian Ruiz’s cross-come-shot away as the champions pushed for an equaliser.
PSG did not have their shooting boots on though as a couple of late efforts went wayward, meaning they are now winless in three league matches and have lost their unbeaten away record.
Strasbourg will be delighted with victory that puts them in a great position to qualify for Champions League football with just two games to play.
Flashscore Man of the Match: Felix Lemarechal (Strasbourg)