The patient was an 86-year-old female who suffered from advanced non-small cell-lung cancer (cT4N3M1, Stage IV). She was treated with combined chemotherapy of gemcitabine and S-1 as first-line therapy. This regimen was performed as a phase I trial for elderly patients with advanced non-small cell lung cancer. The treatment assessment was evaluated as partial response. No toxic events were observed due to this therapy, so she was treated as an outpatient. She was considered to have good quality of life.