A case of idiopathic localized dilatation of the ileum presenting in adulthood and associated with small bowel malrotation, ulceration and bleeding is described. To our knowledge, this is the first such report of this combination of features. The diagnosis was made using a small bowel barium study and intra-operative enteroscopy. Idiopathic localized dilatation of the ileum with ulceration should be considered as a rare small intestinal cause of occult or frank gastrointestinal blood loss in children or young adults.