Abstract: ObjectiveTo investigate the relationship between serum bone marker aminoterminal telopeptide of type Ⅰ collage（NTx）and bone-specific alkaline phosphatase（BALP）expression in prostate cancer with bone metastases and its clinical significance. Methods Seventy-nine prostate cancer patients from Jan 2014 to Dec 2015 were enrolled in this study. According to radionuclide bone scan，bone metastases degree was divided into grade 0-3 by Soloway method. Then the expression of NTx and BALP were measured to determine whether there was difference in different degree of bone metastases. Results There were 32 patients without bone metastases （grade 0），16 patients in grade 1，20 patients in grade 2 and 11 patients in grade 3，respectively. The expression of NTx and BALP in 79 patients were（130.9+16.4）nmoL／mmoL Cr and（234.2+31.6）U／L. The expression of NTx and BALP was closely related to TNM stage，Gleason score，PSA level，but not to age of patients. The serum level of NTx and BALP in bone metastases positive group was significantly higher than that in negative group. The sensitivity of NTx and BALP in the diagnosis of prostate cancer with bone metastases was 87.2％ and 86.7％，and the specificity was 72.1％ and 79.9％，respectively. Conclusion The expression of NTx and BALP has some diagnostic value in the diagnosis of bone metastases of prostate cancer. It can be used as an index to evaluate the progress degree of bone metastases.