Herluin de Conteville (1001–1066), also sometimes listed as Herlevin or Herlwin of Conteville, was the stepfather of William the Conqueror, and the father of Odo of Bayeux and Robert, Count of Mortain, both who became prominent in William's reign.
No contemporary record provides the parentage for Herluin, although much later sources have assigned him parents (such as the otherwise unknown Jean de Conteville (965) and Harlette de Meulan). Herluin was a lord of moderate income and some land on the south side of the river Seine. He was viscount of Conteville, probably so created by his stepson, and held the honour of Sainte-Marie Église, a portion of the county of Mortain. There he founded the Grestain Abbey around 1050 with his son Robert.
Herluin later married Fredesendis, who is named as a benefactor of the Grestain Abbey, and as Herluin's wife in the confirmation charter of the abbey, dated 1189. The abbey was founded by Herluin himself around 1050, in hopes of achieving a cure to his leprosy or some similar disease. Herluin and Fredesendis had two sons: Raoul de Conteville (d. aft. 1089), who later held land in Somerset and Devon, and Jean de Conteville. Little is known of the sons of his second marriage.