Peritoneal encapsulation (PE) is an extremely rare congenital condition in which there is abnormal return of the midgut loop to the abdominal cavity in the early stages of development. It may be present in patients with congenital anomalies like incomplete situs inversus. Pre-operative diagnosis is possible with abdominal CT. A 71year-old man with incomplete situs inversus was admitted to emergency department with symptoms and signs of peritonitis. Computed tomography (CT) of the abdomen showed characteristic features of the PE syndrome. He had exploratory laparotomy performed and arterial occlusion caused ileocaecal ischaemia and PE was observed. Capsule of PE and ileocaecal excision was done. Postoperative recovery was uneventful.