To observe the curative effect of modified Shenling Baizhu decoction in the treatment of bone metastases from lung cancer and to analyze its mechanism. Methods: Sixty cases of lung cancer patients with bone metastases(enrolled in our hospital from January 2008 to August 2014) were selected in the study. According to whether use modified Shenling Baizhu decoction, they are divided into the conventional group (31 cases) and TCM(Traditional Chinese Medicine) group (29 cases), and both of the two groups accepted chemotherapy of allied two medicines containing Pt. 4 mg zoledronic acid + 0.9% Nacl 100 mL intravenous drip, once every three weeks, lasting for 15 weeks. TCM group was given Shenling Baizhu decoction on the basis of the above treatment, 1 dose/day, lasting for 15 weeks. To compare bone pain, peripheral blood Th17 cell percentage changes between the two groups. Results: 1) After treatment, the bone pain VAS scores of the two groups decreased, the decline degree of TCM group is more obvious than that of the conventional group(P<0.05). 2) In the process of follow-up, it was found that the appearance of SREs in TCM group is significantly faster than that of the conventional group with statistical difference(t=4.39, P=0.034<0.05). The incidence of SREs in TCM group decreased obviously than the conventional group with statistical difference(χ2=5.01 P=0.01<0.05). 3)After treatment, the Th17 cells in the two groups decreased significantly than before, and the downward trend was more apparent than the conventional group with statistical differences(P<0.05). Conclusion: Shenling Baizhu power can obviously relieve the clinical symptoms of patients with bone metastases from lung cancer. This may due to the fact that it can decrease Th17 cells in peripheral blood and promote immunity.