In order to establish an acceptable guideline for prevention of perioperative infection following urologic surgery, a questionnaire survey on the theory of antimicrobial prophylaxis (AMP) was conducted among urologists in Japan in February 2004. A reply was obtained from 149 urologists working for institutes located all over Japan from Hokkaido to Kyushu areas. Ninety-two percent of the urologists agreed that AMP should be administered 30 min before an incision, and 44% replied that an additional dose of AMP is required in the case of prolonged intervention. Penicillins or the 1st or 2nd generation cephems were used by 89 to 93% of the urologists in operations not including bowel segments, while 78% preferred such AMP agents in the procedures including bowel segments. AMP was terminated within 3 days in 87% for genital operations, in 70 to 76% for laparoscopic operations, in 54 to 65% for other clean or clean-contaminated operations, and in 24% for operations without the bowel segments. Especially, 58% of the urologists continued AMP for more than 5 days after operations with urinary diversion using the intestine. When compared with the previous questionnaire survey by Shinagawa et al, our survey demonstrated that standard consensus of AMP has spread widely among urologists in Japan, although the recommendations published in Europe and United States are still controversial in Japan. Thus, further well-designed clinical trials are required to establish original guidelines in Japan.