Objective:To observe the clinical curative effects of “Sanjie Tongluo Decoction” combined with radiotherapy on brain metastasis tumor from lung cancer  Methods:76 patients with brain metastasis tumor from lung cancer were equally randomized to the therapy group and the control group. The patients in the therapy group were provided “Sanjie Tongluo Decoction” after radiotherapy, while the patients in the control group were provided radiotherapy and symptomatic treatment, which follow-up 6 months. The efficacy of the solid tumor, progress free survival, tumor markers and immune functions were evaluated between the two groups  Results:① The evaluating effective rate was 94.74% and 89.47% respectively in the therapy group and the control group; There was no significant difference in clinical efficacy between the two groups (P>0.05). ② The progression free survival of brain metastases median was 5.67 months and 3.29 months respectively in the therapy group and the control group; There was significant difference in PFS in between the two groups (P<0.05). ③ Compared between the two groups after the treatment, the serum levels of CEA, CA50 and CA125 were significantly lower in the therapy group than in the control group(P<0.05). ④ Compared between the two groups after the treatment, the NK levels were significantly higher in the therapy group than in the control group(P<0.05)  Conclusion:“Sanjie Tongluo Decoction” can inhibit tumor growth of brain metastases after radiotherapy, and can prolong the progression free survival, as well as can improve the immune functions of the patients.