A duodenal duplication cyst is an uncommon congenital anomaly that is usually encountered during infancy or in early childhood. Duodenal duplication cysts generally appear on the first or second portion of the duodenum and may cause duodenal obstruction, hemorrhage or pancreatitis. Here, we report a case of a duodenal duplication cyst on the second and third portion of the duodenum in an old aged man with obstructive jaundice and acute pancreatitis, which was treated successfully by a surgical excision.