Paraneoplastic syndromes are frequently observed in lung cancer, especially in small cell lung cancer (SCLC). Although there have been many reports on paraneoplastic syndromes, few reports have been published on SCLC that simultaneously produces antidiuretic hormone (ADH) and adrenocorticotropic hormone (ACTH), and these reports described the prognosis of such cases as extremely poor. We herein present a rare case of a Japanese woman with SCLC accompanied by syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and Cushing's syndrome. The survival of the patient was prolonged by the long-term administration of amrubicin.