BACKGROUND In the present study, we assessed the efficacy and morbidity of periprostatic local anesthesia before transrectal ultrasound (TRUS)-guided biopsy of the prostate. METHODS From August 2001 to February 2002, 98 patients underwent TRUS-guided prostate biopsy at the Department of 2nd Urology, Ankara Numune Education and Research Hospital, Ankara, Turkey. Ninety patients who fulfilled the inclusion criteria were randomized into three groups of 30 patients each. Group 1 received no local anesthesia, while group 2 received a periprostatic saline injection 5 min before the biopsy and group 3 received periprostatic local anesthesia with 1% lidocaine. Pain-scale responses were analyzed for each aspect of the biopsy procedure using a visual analog scale. RESULTS There were no differences in pain scores between the three groups during digital rectal examination, intramuscular injection and probe insertion. Mean pain scores during needle insertion in groups 1, 2 and 3 were 5.65 +/- 2.35, 6.25 +/- 2.04 and 3.16 +/- 2.14, respectively. There was no significant difference between the pain scores of groups 1 and 2, whereas pain scores decreased significantly in group 3. CONCLUSION Periprostatic local anesthesia before prostate biopsy is a safe and easy method to increase patient comfort during the procedure.