This phase 1c study will include patients pathologic diagnosis advanced non-small cell lung cancer who had received more than two lines standard treatment, according to NCCN Non-small cell lung cancer guideline, there were no standard treatment scheme for these patients. Approximately 40 patients will be included in the study, patients will received oral ethaselen dispersible tablet, 600 mg bid dose, primary endpoint of this study is 6 week disease control rate(DCR, CR+PR+SD), secondary endpoints include progression free survival(PFS), overall survival(OS), quality of life(QOL) and drug safety.