The unspecific granulomatous prostatitis (GP) is a rare prostate disease. Its relevance lies on the common confusion with prostate carcinoma. Review of 21 cases of unspecific GP, two of which had previously undergone transurethral resection of the prostate. Forty-eight percent of patients developed urinary tract infection prior to GP diagnosis. In 13 patients (62%), prostate carcinoma was suspected after rectal examination of the prostate and transrectal ultrasound. Diagnosis was achieved by histopathology after prostate biopsy and transurethral resection (100%). Prostate Specific Antigen (PSA) was within the normal ranges in all cases that it was performed (six), with the exception of one patient who developed prostate cancer. During follow-up, four patients developed prostate cancer (19%) with an average presentation time of 5.5 years after GP diagnosis.