Simon de Montfort, sometimes known as Simon IV de Montfort, was lord of Montfort-l'Amaury from 1181 to 1188. He was the son of Simon III de Montfort, Count of Évreux and Lord of Montfort-l'Amaury. On his death, Simon III left the comté of Évreux to his elder son Amaury V, and his French properties in Montfort-l'Amaury and Rochefort-en-Yvelines to Simon.