Ruptured aortic abdominal aneurysm associated with horseshoe kidney is seldom encountered. The surgical procedure is complicated by the overlying kidney and the frequent occurrence of multiple aberrant renal arteries, which may arise from the aneurysmic part or from adjacent arteries. One case successfully treated surgically is reported. Renal function declined during the early postoperative period, but returned to preoperative values within three weeks, and remained at pre-rupture levels for the next three months.