Gastroduodenal intussusception is an invagination of part of the stomach through the pylorus and into the duodenum for a varying distance. The lead point of the intussusception is usually a benign gastric tumor such as gastric adenoma. We report a case of gastroduodenal intussusception in a 33-month-old boy presented with nonbilious vomiting and abdominal pain. Laparotomy revealed a gastroduodenal intussusception. After reduction and gastrostomy, a mass measuring $15{ imes}5;cm$ in size, was found at the leading point of the intussusceptum. The mass was resected, and pathological diagnosis showed a gastric hemangiomatosis.