This paper reviews the current advances in molecular genetics and biology of prostate cancer development. Many genetic alterations in prostate cancer have been identified. Some of these changes are early events and occur in prostatic intraepithelial neoplasia and primary cancer of prostate, some others occur in late stages of prostate cancer development. The significant genetic changes for prostate cancer include losses for chromosomes 8p, 5q, 13q, and so forth; gains for chromosomes 8q, 11p, 3q, and so forth; aneusomies of chromosomes 7 and 8; and allelic losses at chromosome regions 8p 12-21, 10q23-24, 16q22.1-24, and 7q31.1-31.2. The alteration of the p53 tumor-suppressor gene plays a role in a subset of advanced prostate cancer. Expressions of TGF-beta receptors, E-cadherin, C-CAM, KAI1, and some integrins have an inverse correlation with either prostatic carcinogenesis or progression of prostate cancer, or both. Protein expression of BCL-2 in prostate cancer is highly correlated with cancer progression and androgen-independent phenotype. More studies need to be performed to identify specific genes for those genetic alterations and to explore the clinical use of the known molecules in prostate cancer.