Objective To explore the diagnostic value of ICTP Tracp 5b and CA15-3 in bone metastasis of breast cancer. Method A retrospective review was performed in 87 breast cancer and 25 breast benign diseases the breast cancer patients were divided into 3 groups 32 patients with bone metastasis 35 patients with no metastasis and 20 patients with extraosseous metastasis. The serum levels of serum ICTP Tracp 5b and CA15 - 3 in 87 patients with breast cancer and 25 patients with benign tumor were measured by enzyme-linked immunosorbent assay ELISA and chemiluminescence immunoassay CLISA . Result The serum levels of ICTP Tracp 5b and CA15-3 were significantly increased in the bone metastasis group P < 0. 05 . The sensitivity specificity positive predictive value and negative predictive value of the parallel combined detection of serum ICTP Tracp 5b and CA15-3 in the diagnosis of bone metastasis of breast cancer were 96. 88% 76. 36% 70. 45% and 97. 67% respectively. The sensitivity of parallel combined detection is significantly greater than ICTP Tracp 5b and CA15-3 P<0. 05 . The sensitivity specificity positive predictive value and negative predictive value of the parallel combined detection were 37. 50% 98. 18% 92. 31% and 72. 97% respectively. The specificity of parallel combined detection is significantly greater than ICTP Tracp 5b and CA15-3 P<0. 05 . Joint diagnosis is more effective than independent diagnosis of the three. Conclusion The detection of serum ICTP Tracp 5b and CA15-3 can significantly improve the diagnostic efficiency of bone metastasis in breast cancer and can be used as an effective laboratory index to assist imaging diagnosis of bone metastasis in breast cancer.