Wagenaar is a Dutch surname shared by the following people:
Bernard Wagenaar, American composerDiderik Wagenaar, a composer and musical theoristJan Wagenaar (waterpolo), a water polo playerJan Wagenaar, an 18th-century Dutch historianJohan Wagenaar, a composer and organistJosh Wagenaar, a footballerRene Wagenaar (1954 -2007), Dutch Professor of Information and Communication TechnologyWillem Albert Wagenaar, a psychologist