Objective To observe the efficacy and adverse reaction of ozone therapy combined with gemcitabine and cisplatin (GP) regimen in patients with advanced non-small cell lung cancer.Methods Fifty-five patients with advanced non-small cell lung cancer were enrolled and allocated to treatment group (28 cases) and control group (27 cases).The patients in treatment group received ozone therapy combined with GP regimen,and the patients in control group received GP regimen only.The efficacy,quality of life,adverse reaction and cellular immune function after treatment was compared between two groups.Results There was no significant difference in the efficacy between two groups (P ＞ 0.05).The quality of life after treatment in treatment group was better than that in control group (P ＜ 0.05).The liver function damage in treatment group was lower than that in control group (P ＜ 0.05).The cellular immune function in treatment group was stronger than that in control group (P ＜ 0.05).Conclusion Ozone therapy combined with GP regimen can effectively alleviate adverse induced by GP regimen chemotherapy and significantly improve the quality of life in patients with advanced non-small cell lung cancer.