Despite the home side's positive start, Toulouse looked dangerous on the break and Dragos Grigore's header came close, but missed the target.
Grigore then crossed for Martin Braithwaite to head wide as Toulouse grew into the game.
It was Montpellier who went in front, however, when Mounier fired in just before half time.
After the break, Mounier looked to get himself a second goal and dragged a shot just wide of the post.
Camara was the one to eventually seal the win with a strike in the final minutes of the match.