Abstract A 14-yr-old, previously healthy boy presented with massive lower GI hemorrhage. After the routine endoscopic and radiological evaluation, laparotomy and intraoperative colonoscopy revealed multiple polyps in the colon. A hemicolectomy was performed because of the severity of hemorrhage. A diagnosis of juvenile polyposis was made based upon histological findings and the family history. This is an extremely unusual presentation of juvenile polyposis and has been reported only once before. The clinical features, diagnosis, and therapeutic options for juvenile polyposis are discussed. Juvenile polyposis, although a rare condition in the pediatric population, should be considered in the differential diagnosis of life-threatening GI hemorrhage.