Saint-Gratien (French pronunciation: [sɛ̃ ɡʁasjɛ̃] ⓘ) is a commune in the Val-d'Oise department, in the northern suburbs of Paris, France.

It is located 13.8 km (8.6 mi) from the center of Paris.

On August 7, 1850, a part of the territory of Saint-Gratien was detached and merged with a part of the territory of Deuil-la-Barre, a part of the territory of Soisy-sous-Montmorency, and a part of the territory of Épinay-sur-Seine to create the commune of Enghien-les-Bains.

Saint-Gratien is served by Saint-Gratien station on Paris RER line and by the bus number 138 going to Paris — Porte de Clichy.

This Val-d'Oise geographical article is a stub.