The patient was a 62-year-old woman who had undergone modified radical mastectomy for right breast cancer 19 years before. She was examined at our hospital for cough and hoarseness. After PET-CT and bronchoscopy, she was diagnosed with stage IIIB non-small cell lung cancer. Radiation therapy and cisplatin plus pemetrexed therapy were effective, and she made a recovery from a life-threatening conditon. During observation, a skin nodule was noticed on her right chest wall, and excisional biopsy revealed a skin metastasis from breast cancer. A transbronchial lung biopsy(TBLB)specimen was reexamined, and the lung lesion was shown to be metastasis from breast cancer. By changing to endocrine therapy, the disease has been effectively controlled.