Abstract: Objective:To evaluate the clinical value of radioactive nuclide strontium chloride (89SrCl 2) combined with 99Tc-MDP in treating patients with breast cancer and osseous metastasis. Methods:A total of 80patients with breast cancer and experiencing bone pain from osseous metastasis were randomly categorized into three groups. 22patients were treated with 99Tc-MDP (99Tc-MDP group), 30were treated with 89SrCl 2 (89SrCl 2 group), and 28were treated with the combination therapy of 89SrCl 2 and 99Tc- MDP (combination group). The analgesic effect, remission of bone metastases, and quality of life of patients in the three groups were observed before and after treatment. Side effect was also monitored. Results: In the combination group, the overall pain relief rate and the increase rate of life quality score were 92.9% (26/28) and 78.6% (22/28), respectively. The combination group was statistically significantly different from the two single- treatment groups (P <0.05). The effective rate of metastatic lesions was 46.4% (13/28) in the combination group, which was significantly higher than that in the 99 Tc-MDP group ( 18.2%,4/22; P <0.05). The effective rate of metastatic lesions was not significantly different between the combination and 89 SrCl 2 groups (33.3%,10/30) ( P>0.05). Conclusion:The treatment of 89SrCl 2 com -bined with 99Tc-MDP can increase the analgesic effect and significantly improve the curative effect without overt side effects in patients with breast cancer and bone metastasis.