Objective To explore the clinical value of serum prostatespecific antigen (PSA), free PSA/ total PSA (fPSA%), gastral release peptide (PSAD) in the diagnosis of prostate cancer and bone metastasis.Methods The data of 108 patients with prostate cancer (PCA) and 25 patients with benign prostatic hyperplasia (BPH) in our hospital were retrospectively analyzed. The observation group was divided into non bone metastasis (NBM) and bone metastasis (BM). The serum PSA, FPSA and ProGRP of all subjects were detected, and the values of fPSA% and PSAD were calculated according to the examination results. The value of the three and combined detection (FPSA%+PSAD+ProGRP) in the diagnosis of PCA was analyzed by receiver operating characteristic curve (ROC).Results The median level of fPSA% in PCa group was significantly lower than that in BPH group (P＜0.05). The median levels of PSAD and proGRP in PCa group were significantly higher than those in BPH group (P＜0.05). The area under the curve (AUC) of subjects working characteristic curves of fPSA%, PSAD, proGRP and the three in the combined diagnosis of PCa were 0.755, 0.721, 0.715 and 0.809 respectively. Combined detection and diagnosis ability was the best, and there are significant differences in diagnostic ability of each indicator (P＜0.001). The AUC values of fPSA% in NBM group, PSAD and proGRP were respectively 0.690, 0.676 and 0.660, which reflected the ability of early and midstage PCa diagnosis. Diagnosticboundary value was adopted to facilitate early diagnosis and early treatment. There was no statistical significance in the diagnostic ability of PSA (AUC=0.585, P=0.148) in THE NBM group (P＞0.05) .The AUC values of fPSA% in BM group, PSAD and proGRP were 0.905, 0.894 and 0.863, respectively. The diagnostic boundary value was adopted to help predict, reduce or delay the occurrence of bone metastasis. The AUC value of PSA in BM group was the highest (AUC=0926), and the diagnostic ability was the best among the four single indicators.Conclusion fPSA%, PSAD and proGRP have high clinical value in the diagnosis of PCa and especially in early PCa. The combined detection of three indexes can significantly improve the diagnostic ability of PCa. With the development of TNM stages, the diagnostic abilities of tumor markers fPSA%, PSAD and proGRP are more obvious.