A two-year-old male with total tubular duplication of the colon and distal ileum combined with transmesenteric hernia is presented. Recurrent abdominal pain, distention of the abdomen and chronic constipation were the main complaints. A side-to-side anastomosis created through the lowermost part of the common wall of the duplication and colon proper, plus closure of the mesenteric defect and excision of the duplicated ileal loops relieved the patient of all symptoms. Postoperative stagnation of the stool in the closed hollow end of the duplication caused distention developing into a prolapsing pouch which required excision by transanal approach six years after the laparotomy.