Abstract: Objective: To investigate the effects and adverse reactions of zoledronic acid combined with chemotherapy in the treatment of malignant tumor with bone metastases.Methods: Sixty-four malignant tumor patients with bone metastases were randomly divided into the control group and trial group(32 cases each group).The control group and trial group were treated with single chemotherapy and zoledronic acid combined with chemotherapy,respectively.The chemotherapy regimens of two groups were the same.Results: The totally effective rates of curing pain in trial group and control group were 81.3% and 46.9%,respectively.The totally effective rates of controlling bone metastases in trial group and control group were 62.5% and 28.1%,respectively.The treatment effect in trial group was better than that in control group(P<0.01),no serious adverse reaction in two groups was found.Conclusions: The therapeutic effect of zoledronic acid combined with chemotherapy is better than that of single chemotherapy.The adverse reaction of zoledronic acid combined with chemotherapy is slight,and the patient is well-tolerated.