A 3-year-old boy visited the hospital because of cyclic abdominal pain and recurrent vomiting without hematochezia. Abdominal ultrasound showed transverse colo-colic intussusception and air reduction was performed successfully. After 1 month, He revisited the emergency room for painless hematochezia. Vital signs, physical examinations and laboratory findings were normal. Colonoscopy showed a 1-cm pedunculated polyp in the transverse colon and polypectomy was performed. Pathologic examination revealed it to be a juvenile polyp. The patient was stable and discharged the next day of polypectomy without complications. Juvenile polyp in transverse colon manifested by intussusception in 3-year-old child is rare case. So if colo-colonic intussusception is found even in young child, a thorough diagnostic test is required to find a pathologic lead point.