Aortoenteric fistula is an uncommon cause of upper gastrointestinal bleeding, which is life-threatening if not treated. This complication may occur even months to years after surgery [Mitchel 1995]. It is commonly observed in patients who have undergone previous aortic surgery and rarely occurs in patients with a history of gastrointestinal tract surgery [Brock 1953]. The diagnosis of aortoenteric fistula depends on a high level of clinical suspicion. Herein, we report a case of a 53-year-old man who underwent surgical treatment because of new-onset severe gastrointestinal bleeding that was related to an aortoenteric fistula.