The recent availability of an automated core biopsy gun has made the performance of core biopsies of the prostate easier and better tolerated. A prospective study was conducted to compare the efficacy of fine needle aspiration to core biopsy with the gun. Among 94 patients subjected to both biopsy techniques at the same visit 30 (32%) had a positive diagnosis of prostate cancer. Core biopsy was positive in these 30 patients (100%), while fine needle aspiration was positive in 21 (70%). This study suggests that core biopsy with the gun is superior to fine needle aspiration in the diagnosis of prostate cancer.