To explore the role of Fas,FasL in pathogenesis of prostatic cancer (Pca), expression of Fas and FasL in 49 cases of Pca, 22 cases of BPH and 14 cases of normal prostate(NP) was detected by immunohistochemical SP method. The results were as follows: ①Fas, FasL were expressed in all the examined tissues; ②The expression of Fas was strongest in BPH specimens and weekest in Pca tissues ( P 0 05);④The expression of Fas in 17 cases of androgen dependent Pca tissues was more marked than that in 9 cases of androgen independent Pca tissues( P