Objective: To study the effect of antioxidant thiopronine on chemotherapy for advanced non-small cell lung cancer. Methods: Case data of patients from the chemotherapy department of Jiangsu Cancer Hospital from June 2004 to December 2007 were screened. Patients with advanced non-small cell lung cancer who used thiopronine in combination with first-line chemotherapy were selected as the thiopronine combination chemotherapy group (Group A), and an equal number of patients with advanced non-small cell lung cancer who did not use thiopronine in combination with first-line chemotherapy were randomly selected as the control group (Group B). The efficacy, adverse effects and survival of chemotherapy were analyzed and compared between the two groups using Stata 8.0 statistical software. Conclusion: The combination of the antioxidant thiopronine with first-line chemotherapy for advanced non-small cell lung cancer did not significantly improve the recent efficacy of chemotherapy and prolong survival time, but it could reduce chemotherapy-induced leukocyte reduction and improve the one-year survival rate.