Poissy is a commune in the Yvelines department in the Île-de-France in north-central France. It is located in the western suburbs of Paris, from the centre of Paris.
In 1561 it was the site of a fruitless Catholic-Huguenot conference, the Colloquy at Poissy. It is known for hosting successively the Automobiles Gregoire, Matford, Ford SAF, Simca, Chrysler, Talbot factories, and now hosts one of France's largest Peugeot factories. Inhabitants are called Pisciacais.
The " Simca Poissy engine" was made here.