William de Warenne, 1st Earl of Surrey, Seigneur de Varennes († 1088), is a Norman nobleman who is created Earl of Surrey under William II 'Rufus'.

He is one of the few who is documented to have been with William the Conqueror at the Battle of Hastings in 1066.

At the Domesday Survey he holds extensive lands in thirteen counties including the Rape of Lewes in Sussex (now East Sussex).