Arterial involvement in Behçet's disease is rare, occurring in various locations with multiple clinical expressions. When Behçet's disease is associated with large arteries, lesions are usually in the form of aneurysms or occlusions. The simultaneous occurrence of these two lesions is even more unusual. We present a case of Behçet's disease in which arterial involvement included an iliac artery thrombosis and an asymptomatic aneurysm of the infrarenal abdominal aorta. Behçet's disease must be considered in the diagnosis of any unexplained inflammatory arteriopathy. Surgery is indicated for the majority of aneurysms and severe symptoms. The postoperative follow-up is based on noninvasive radiologic examinations.