Plaisir (French pronunciation: [plɛziʁ] ⓘ) is a commune located in the heart of the Yvelines department in the Île-de-France region in Northern France.

It borders among others on Élancourt (south), Trappes (southeast) and Les Clayes-sous-Bois (east).

Its varied territory is characterised by large agricultural plains, many green spaces and a forest area that together occupy half of its surface.

Plaisir is the twelfth commune of the Yvelines department in terms of population, with nearly 31,000 inhabitants.

This commercial activity has been a boon for local tax revenues, but also led to congestion of its roads.