Prostate inflammation, also known as prostatitis, is defined as a pathological inflammatory change in prostate tissue. Based on clinical and laboratory findings, it can be categorized into different groups. Recent prostate inflammation researches are focusing on the immunological events within prostate. Despite the etiology of inflammation, prostate may go through similar serous and cellular reactions to defend itself from all types of danger signals. These reactions may have further interaction with different prostate pathologies, such as benign prostate hyperplasia or prostate cancer. Potential treatment options may be derived from understanding of inflammatory mechanism.