Objective:To investigate the in situ expression of human telomerase reverse transcriptase (hTERT) in benign prostatic hyperplasia (BPH),prostate intraepithelial neoplasia (PIN) and prostate carcinoma (PCa) tissues and its clinic significance. Methods:Using immunohistochemical method,the expression of hTERT was examined in 43 specimens of prostate tissues,including 15 cases of BPH,11 cases of PIN and 17 cases of PCa. The association of Gleason score and expression of hTERT was explored. Data were analyzed by Fisher’s Exact Test and Spearman’s rho analysis. Results:1. The hTERT protein was expressed in 15 out of 17 PCa cases (88.24%),4 out of 11 PIN cases (36.36%),and 0 of 15 cases of BPH . A significant difference of expression was observed in the comparison of each two groups(all P < 0.05). 2. The intensity of hTERT expression in prostate carcinoma increases along with the Gleason score. The intensity of hTERT expression in prostate carcinoma was positively related to the Gleason score(P < 0.05). Conclusion:The hTERT protein is highly expressed in prostate tissue,which may be applied as a biomarker for differential diagnosis between benign and malignant lesions. The intensity of hTERT expression in PCa increases along with the Gleason score. PIN patients with positive expression of hTERT should be closely observed and fellowed up.