Behçet's syndrome represents a multisystemic disease with vasculitic changes. We here describe a patient with Dieulafoy's ulcer and oral, genital and bronchial mucosal lesions who met the criteria of incomplete Behçet's syndrome. The rare observation of Behçet's syndrome presenting with Dieulafoy's ulcer in our patient raises the question as to whether this type of ulcer, usually caused by a developmental malformation of a submucosal gastric artery, may occasionally be due also to submucosal aneurysms that result from a vascular inflammation.