Idiopathic small bowel ulceration distal to the duodenum is rare. Less than 5 % of the reported cases were in children. In the majority of the patients, a single ulcer of unknown cause is found in the jejunum or ileum. The diagnosis is difficult and usually made at the time of surgical exploration for complications, such as perforation, hemorrhage or obstruction. We treated a pediatric patient with perforation of an idiopathic ileal ulceration. The child was an 11-year-old boy who sustained blunt abdominal trauma. The involved ileal segment was resected. Pathologic findings were compatible with idiopathic small bowel ulceration. The clinical and pathological aspects of idiopathic ulcerations are discussed, and the literature reviewed.