Saclay (French: [saklɛ] ⓘ) is a commune in the southwestern suburbs of Paris, France.

It is located 18.7 km (11.6 mi) from the centre of Paris.

It is best known for the large scientific facility CEA Saclay, mostly dealing with nuclear and particle physics.

Saclay is served by no station of the Paris Métro, or suburban rail network (RER).

This station is located in the neighboring commune of Orsay, 3.2 kilometres (2 miles) to the south of the town center of Saclay.