A 34-year-old woman with a history of infectious enteritis one year ago. Colonoscopy showed intestinal constriction and inflammation. She was referred to our hospital for further treatment. We suspected that she had small intestinal endometriosis and performed laparoscopic ileocecal resection. Surgical findings showed bending and adhesion of the terminal ileum. A pathological examination of the resected ileum showed infiltration by endometrial tissue through almost the entire wall from serosa to muscularis of the ileum. The postoperative course was uneventful. Endometriosis should be considered as a differential diagnosis with a high index of suspicion in premenopausal women.
