In Manchester, the match looked to be heading to a goalless stalemate until Griedge Mbock brought down Khadija Shaw in the box.
The Jamaica international kept her composure to convert the spot-kick in the 85th minute.
But the visitors struck back with two minutes remaining on the clock as Tara Elimbi Gilbert broke down the right and slotted home to level.
The result leaves PSG sixth in the table on five points, while a third consecutive draw means Man City lie two points further back in 10th.