The Château d'Écouen is a historical château in the city of Écouen, north of Paris, France. The château was built between 1538 and 1550 by the architect Jean Bullant for Anne de Montmorency, who was made Connétable de France in 1538. Anne de Montmorency had inherited the château in 1515, and his building campaigns were informed by his first-hand experience in overseeing royal works at Saint-Germain-En-Laye and Fontainebleau.
Jean Bullant is likely to have been the architect, for he was commissioned to design the Grand Constable's tomb, but it has also been suggested that Pierre Tâcheron had a hand in the château's design. The colossal order is rare in French architecture before Bullant; his characteristic use of it might be its first appearance in France here, on the pavilion on the court side.