Abstract: Objective:To evaluate the expression levels of androgen receptor coregulators in prostate cancer and their significance in predicting the prognosis of patients treated with endocrine therapy. Methods:Clinical and pathological data of 116 cases of prostate cancer treated with endocrine therapy were collected between January 2000and November 2007 in our hospital. The expression of steroid receptor coactivator- 1 (SRC- 1) and silencing mediator for retinoid and thyroid hor -mone receptors (SMRT) were detected with immunohistochemical EnVision method in paraffin-embeded tissue. Relation-ship of SRC- 1 and SMRT expression with clinicopathologic characteristics was investigated through χ2 test or Fish exact test. Clinicopathologic factors and protein expression that influence the progression-free survival of prostate cancer pa -tients were analyzed with univariate (log-rank test) and multivariate Cox proportional hazard model. Results:SRC-1 expres-sion was significantly associated with several conventional prognostic factors. Univariate analysis showed that clinical stage, Gleason sum, pretreatment serum PSA level and SRC- 1 expression were significant predictors for PSA progression after endocrine therapy. Multivariate analysis revealed that SRC- 1 expression and clinical stage were independently corre -lated with PSA progression after endocrine therapy. Conclusion:SRC 1 is an independent prognostic factor for prostate can -cer patients treated with endocrine therapy. Combined evaluation of SRC- 1 expression and clinical stage would be particu -larly useful for predicting the outcome of prostate cancer patients treated with endocrine therapy.