Ranulf II of Poitiers (850–August 5, 890) was Count of Poitiers between 866 and 890. Ranulf became Duke of Aquitaine in 887 and styled himself king of Aquitaine from 888 to his death. Ranulf was son of Ranulf I of Poitiers and Bilichilde of Maine. He married an Ermengarde and by her had a son, Ranulf III, that succeeded him as count of Poitiers. His illegitimate son Ebalus succeeded him in Aquitaine and, in the death of Ranulf III, in Poitiers too.