Willem van Ruytenburch, lord of Vlaardingen and Vlaardingen-Ambacht (1600–1652) was a member of the Dutch gentry and Amsterdam patriciate of the Dutch Golden Age. He became an alderman of Amsterdam and joined the Schutterij (city guard) of Frans Banninck Cocq. Willem was featured, as a lieutenant, in Rembrandt's 1642 painting The Night Watch for which he is now probably most famous.