Objective：To observe the clinical effect of fire needle at Sihua point for patients undergoing chemotherapy with non-small cell lung cancer and investigate its possible mechanism by detecting the contents of interferon-γ(IFN-γ)and interleukin 4(IL-4)in serum.Methods：Divided 60 cases of patients with non-small cell lung cancer into two groups randomly，30 cases in each group.The control group was treated with routine chemotherapy in which TP，GP，DP and AP methods were used for chemotherapy，while the observation group was additionally given fire needle at Sihua point(Geshu and Danshu points)based on the routine chemotherapy.The treatment of the two groups lasted for 21 days.After treatment，the objective index of tumor was evaluated by RECIST criteria，and the contents of IFN-γ and IL-4 in serum were detected respectively before and after treatment.Results：After treatment，ORR was 20.0%and OSD was 73.3%in the observation group.There was no significant difference being found in the respective comparison of ORR and OSD between the two groups(P＞0.05).After treatment，IFN-γ in the control group was lower than that before treatment while IL-4 was higher，differences being significant(P＜0.05).After treatment，IFN-γ in the observation group was higher than that before treatment while IL-4 was lower，the difference being significant(P＜ 0.05).IFN-γ and IL-4 were negatively correlated with the counterparts respectively in the two groups.After treatment，the level of IFN-γ was positively correlated with the RECIST evaluation；IL-4 in serum was not correlated with RECIST evaluation.Conclusion：The therapy of fire needle at Sihua point possibly adjusts Th1/Th2 balance to reverse Th1 to drift to Th2 by regulating the contents of IFN-γ and IL-4 in serum.