The detection and treatment of prostate cancer has been markedly improved by the use of Prostate-Specific Antigen (PSA) as a serological biomarker for disease. However, even after surgical intervention and hormone ablation therapy, a significant proportion of patients progress to advanced metastatic disease, for which there is no cure. An important goal has become the identification of antigens in advanced stage prostate cancer that represent targets for therapy. Recently, great progress has been made to utilize immunological therapies to treat cancer. Monoclonal antibody therapy has been successfully approved for the treatment of breast cancer and B-cell lymphoma, and multiple clinical trails are currently in progress in a variety of cancers, including prostate cancer. Pre-clinical and clinical studies are also underway to evaluate cancer vaccine approaches directed against antigens that are highly expressed in prostate and other cancers. This article describes several target antigens expressed in prostate cancer and immunological approaches directed against them that may be effective for treating prostate cancer patients.