Poissy is a commune in the western suburbs of Paris, France. It is located 23.8 km (14.8 miles) from the center of Paris.

In 1561 it was the site of a fruitless Catholic-Huguenot conference, the Colloquy at Poissy. It is known for hosting successively Automobiles Gregoire, Matford, Ford SAF, Simca, Chrysler, Talbot factories, now one of France's largest Peugeot factories. Inhabitants are called Pisciacais.