Postoperative intussusception (POI) is an uncommon but important cause of postoperative intestinal obstruction. We describe three cases of intussusception, which developed after major abdominal surgery. Two of the patients were premature newborns whose conditions were complicated by necrotizing enterocolitis and accepted ostomy. The other case involved a patient with Hirschsprung's disease who had had a previous colostomy and accepted Duhamel pull through procedure. Postoperative intussusception is a rare complication of pediatric abdominal surgery and may occur in premature infants. The ostomy may be the predisposing factor of these patients.