Three patients with an uncommon complication of Crohn's disease are presented. A free perforation of the diseased terminal ileum was found at laparotomy in all patients. Pneumoperitoneum was not seen on x-ray. They all underwent emergency surgery with a tentative diagnosis of acute appendicitis and/or generalized peritonitis. The surgical management is described.The literature was reviewed regarding free perforation of the small bowel in Crohn's disease. The clinical and radiologicai findings of this condition are described. Simple suture of the perforation should be avoided because of the high mortality (33%) and complications rates (44%) recorded in the literature with this surgical procedure. According to the limited world experience, resection of the diseased bowel is the treatment of choice in these patients.