PSG now four points clear at the top of Ligue 1.
Dembélé scored two goals in the match.
The victory took place at home against Toulouse.
Briefing: Dembélé at the double as league leaders PSG down Toulouse
Strategic angle: Paris Saint-Germain secured a 3-1 victory over Toulouse, with Ousmane Dembélé scoring twice to extend their lead in Ligue 1.