The prognosis in prostate cancer depends on several clinical-morphological factors, such as Gleason score, pTNM and preoperative PSA level. Reliable biological markers are being sought to supplement clinical-morphological data in order to better predict prognosis and to select an individualized therapeutic option. The aim of this study was a comparative analysis of the expression of biological markers, such as Hif-1α, bcl-2, p53, Ki-67, cyclin D1 and CD44 in BPH and prostate cancer, as well as examining their association with standard prognostic factors in prostate cancer. The immunohistochemical analysis was made on 82 formalin-fixed, paraffin- embedded tissue blocks: 43 prostate cancer specimens derived from patients who had undergone radical resection, and 39 prostate bioptates derived from patients with BPH. A positive correlation was demonstrated between Gleason score and the expression of both Hif-1α (R = 0.32, p 〈 0.05) and Ki-67 (R = 0.30, p 〈 0.05). Additionally, a negative correlation was demonstrated between tumor stage (pTNM) and bcl-2 expression (R = -0.35, p 〈 0.05). Hif-1α as a hypoxia marker and Ki-67 as a proliferation marker, both correlated with Gleason score, may constitute important additional prognostic indicators in prostate cancer patients.