Foreign body ingestion is not an uncommon problem . The accidental ingestion of fi sh bones may sometimes lead to penetration injuries with complicating abscess formation. fish bones are usually invisible on plain X-ray. A computed tomography (CT) scan of the abdomen is helpful to determine the cause of abdominal pain. We present the case of a 78-year-old man who had periumbilical area pain and dyspepsia . The computed tomography (CT) demonstrated a 5cm sized cystic lesion with wall enhancement and adjacent fat infi ltration in periumbilical mesentery. An periumbilical mesentery abscess was diagnosed and after colonoscopy, a foreign body, which proved to be a fi sh bone, was removed. The man could not remember swallowing this fi sh bone.