The purpose of this presentation is to report three adult patients with aortoenteric fistula whose initial presentation was abdominal pain and digestive bleeding. We stress the low incidence of this disease as a cause of digestive bleeding, its high mortality and the need of high clinical suspicion for its diagnosis. We discuss the different sites of the aortoenteric fistulas, probable physiopathological mechanisms that generate them and their elevated association with the presence of vascular prostheses.