A rare case of solitary ileal duplication cyst accompanied by heterotopic pancreas in the terminal ileum is presented. An 8 year old boy with an ovoid shaped, elastic soft and pendant-growing ileal duplication cyst associated with aberrant pancreatic tissue but not communicating with the lumen of the ileum, underwent an adhesiotomy for a small intestinal adhesion that caused bowel obstruction. The obstructive state of the intestine seemed to be caused by an inflammation of the duplication cyst which was 4.5 x 2.7 x 2.5 cm and oval in shape. Excision of the cyst and the heterotopic pancreas was curative. The histological findings were identical to heterotopic pancreas accompanied by ileal duplication without any clinical features of heterotopic pancreas. A review of the literature is presented along with the author's experience in a case of ileal duplication cyst associated with heterotopic pancreas located in the ileum.