This study was made to explore the expressions of P53, P16, Bc1-2 and Bax protein in prostate carcinoma and their relations to histopathological grading, clinical staging and prognosis of this tumor. Immunohistochemical staining method was used to assess the expression of P53, P16, Bc1-2 and Bax protein in 51 cases of prostate carcinoma. The positive rates of P53, P16, Bc1-2 and Bax proteins were 31.37%, 54.90%, 21.57% and 74.51% respectively. The expression of P53 and Bc1-2 showed positive correlation with the histopathological grading and clinical staging of this tumor (P < 0.05). However, the expression of P16 and Bax showed negative correlation with the grading and staging of the tumor (P < 0.05). The expression of P53 protein correlated with the survival rate of these patients. There was a relation between P53 and Bc1-2, and a relation between Bc1-2 and Bax also (P < 0.05). These findings suggest that expressions of P53, P16, Bc1-2 and Bax may be helpful to the grading, staging and prognostic evaluation of prostate carcinoma.