[en] Objective: This study was to evaluate the efficacy of Samarium-153-EDTMP in breast cancer with bone metastases. Methods: 438 cases with advanced breast cancer that had metastatic bone pain were treated with ¹⁵³Sm-EDTMP at a dosage of 25.9 MBq/Kg once a month. One course of treatment was 3 to 4 times. Results: The results were evaluated according to the degree of pain relief, mobility, analgesic intake and general feeling. 52.7% (231/438) of patients got complete remission and 33.8% (148/438) incomplete remission. There was no response in the remaining 13.8% (59/438). 52 cases had improved bone scan findings. Conclusion: Palliative treatment of metastatic bone pain from breast cancer with ¹⁵³Sm-EDTMP improves the quality of life and may be safely repeated with the same benefit and without significant myelosuppression