Angiodysplasia is an important vascular lesion of the gastointestinal tract , located at the site of ectasia of intestinal submucosal veins and overlying mucosal capillaries. It is a major cause of morbidity from gastrointestinal bleeding in old age, but rather rare in children. Its cause is still unknown, though is mostly considered to be acquired as a result of a degenerative process associated with aging. We experienced a case of colonic angiodysplasia in 14-year old boy, diagnosed by colonoscopy. The patient had a history of repeated hematochezia for a year. This report summarized our case and reviewed the literature.