Gastroduodenal intussception is defined as invagination of a portion of the full thickness of the stomach into the duodenum. A case of gastroduodenal intussception with pedunculated hamartomartoma in the region of pyloric vestibule is presented because of its provacative nature, relative rarity, and unnecessary errors in radiological diagnosis. The purpose of this paper is stressed to outstanding radiological criteria rather than rarity of hamartoma of the stomach.