PURPOSE: Intestinal duplications are rare congenital malformations that may require surgical intervention. This study attempted to elucidate the clinical characteristics and the management of this disease. METHODS: We reviewed the experience of 13 intestinal duplications confirmed with postoperative pathologic reports from January 1989 to September 2001 at Seoul National University Children's hospital. RESULTS: Nine patients were female and 4 were male. Ages ranged from a few days to 5 years (61.4% younger than 1 year). The most common symptom was a vomiting. The major diagnostic method recorded was abdominal ultrasonography. The location of the 12 cystic duplicaions was the ileum in 7 cases, the anus in 2 cases, the duodenun in 1 case, the jejunun in 1 case and the rectum in 1 case. A tubular duplication from the transverse colon to the anus with communication was found in one case. The diameter of the cystic duplications averaged 3.45 cm, and the average length of the tubular duplication was 40 cm. Treatment used was resection and anastomosis of the involved intestine in 8 cases, septostomies in 2, anoplasty in 1, marsupialization in 1 and transanal excision in 1. There were no postoperative complications or mortality experienced. Gastric mucosa was found in 3 of 7 ileal duplications, small intestinal mucosa was found in the duodenal duplication, and squamous epitheliums were found in the rectal and anal duplications. CONCLUSION: Congenital intestinal duplication presents as an intestinal obstruction or an abdominal mass in childhood. Abdominal ultrasonography is a major diagnostic method and surgical intervention is mandatory.