Prostate cancer remains one of the most prevalent malignant tumors in males, with persistently high incidence and mortality rates. In recent years, immunotherapy has emerged as a novel therapeutic approach, demonstrating remarkable efficacy in treating various malignancies and gaining widespread application in prostate cancer. However, it still faces numerous challenges. This review summarizes the primary immunotherapeutic strategies and combination approaches for prostate cancer. Current research emphasizes the necessity to further elucidate the mechanisms of the prostate cancer tumor microenvironment, identify more effective biomarkers, optimize combination regimens, and implement personalized treatment to enhance the safety and efficacy of immunotherapy.