An adult, intact male domestic shorthair presented for preputial swelling and urinary incontinence. A caudal abdominal mass was palpated. A transabdominal ultrasound examination showed severe prostatomegaly with abnormal tissue extending along the urethra. The cat was euthanized due to the owner's financial constraints and the veterinarians' suspicion of a poor long-term prognosis. Biopsies showed chronic active inflammation of the prostate, bladder, kidneys, ureters, penis, and prepuce most consistent with a chronic infectious process. Reports of feline prostatic disease of any kind are rare. Chronic prostatitis may have a more favorable prognosis than feline prostatic adenocarcinoma, currently the most commonly reported disease of the feline prostate.