Abstract: Objective To explore whether the administration of Glycididazole natrium (CMNa) in advanced nonsmall cell lung cancer (NSCLC) patients can enhance the chemo-sensitivity and to evaluate its safety. Methods Patients with NSCLC confirmed by pathologic and/or cellular evidences were randomly divided into to chemo-sensitivity enhancing (CSE) group (25 patients, TP treating and CMNa) or control group (31 patients, TP treating alone). The chemo-therapy efficacy and side-effects were recorded and analyzed. Results Compared with the control group, the patients in the CSE group seems had a higher total effective rate with no significant difference (40.0% in CSE group, 35.5% in control group, P>0.05). The mean survival time, 1 year and 2 years survival rate of the CSE and control group was 19.4 months, 19.5 months, and 70.8%, 40.1%, and 69.4%, 32.7% respectively. The main side-effects were hematologic toxicity, nausea and vomiting, muscular soreness, peripheral neurotoxicity and renal dysfunction. There was no significant difference existing between groups. Conclusion Administration of CMNa may enhance the chemo-sensitivity of NSCLC without obvious side effects. However, large scale clinical trial is required for the further confirmation of short and long term efficacy.