Behcet's disease is a multisystemic disease characterized by ulcers (aphthae) of the mouth & genitalia, inflammatory eye disorders forming the so-called triple syndrome. Sometimes, only two of the three manifestations are present. Recently, the authors have experienced a case of aphthous lesion in the oral mucous membrane and genitalia. This paper was written for the purpose of reporting the case treated by cytoxan and reviewing literatures on this subject.