William de Warenne, 1st Earl of Surrey, Seigneur de Varennes (died 1088), was a Norman nobleman who was created Earl of Surrey under William II 'Rufus'. He was one of the few who was documented to have been with William the Conqueror at the Battle of Hastings in 1066. At the Domesday Survey he held extensive lands in thirteen counties including the Rape of Lewes in Sussex (now East Sussex).