Marly-le-Roi is a commune in the Yvelines department in the administrative region of Île-de-France, France. It is located in the western suburbs of Paris, 18.4 km from the centre of Paris.
Marly-le-Roi was the location of the Château de Marly, the famous leisure residence of the Sun King Louis XIV which was destroyed after the French Revolution. The Marly-le-Roi National Estate and Park now occupies much of the grounds of the former château, including restored waterways and lawns.