A 29 year-old man with a previous history of peptic ulcer, post subtotal gastrectomy and Billroth-Ⅱ anastomosis, suffered from tarry-bloody stool and was admitted to the Far-Eastern Memorial emergency room. Component therapy was administered. Esophagogastroduodenoscopy did not discover the cause of the bleeding. Colonoscopy identified a 3 cm long fishbone with some serosanguinous fluid and blood clot at the descending colon. The fishbone was grasped with a snare and removed. The post-operative course was uneventful without further bleeding. The patient was discharged 3 days later. During a one year follow-up, no further bleeding was noted.