Objectives : The NMOC 3-Way Catheter® (NMOC) functions as a conventional urethral catheter, but has a lumen for injection of local anesthetics. Available in Japan, the NMOC is reported to alleviate catheter-associated postoperative discomfort and pain at the time of catheter withdrawal. We investigated the safety and efficacy of pain reduction of the NMOC compared with a conventional urinary catheter during high-dose-rate brachytherapy (HDRB) of the prostate. Methods. : The NMOC (16 Fr, 10-ml cuff) was placed in 20 patients undergoing HDRB (NMOC group) ; 10 ml of 4% lidocaine was administered to the urethra through the injection port. A conventional catheter (16 Fr, 10-ml cuff) was placed in 10 additional HDRB patients (control group). Patients assessed their pain with a numerical rating scale (NRS) and face scale (FS). Higher scores indicated greater pain. The Mann-Whitney U test was used for statistical analysis ; p<0.05 was considered statistically significant. Results : There were no differences in patient background between the control and NMOC groups. Pain scores were significantly lower in the NMOC group than in the control group both at the time of catheter exchange and during catheter manipulation. The frequency of analgesia use through the following morning did not decrease with NMOC use. However, the median time before first use of analgesics for catheter traction-associated pain was about 2 hours longer with NMOC use than in the control group. Median pain scores at the time of drug injection were 0 according to both NRS and FS. No complications occurred with NMOC use. Conclusion : The NMOC was safely used in patients after HDRB of the prostate, and effectively reduced pain during catheter exchange and catheter manipulation better than a conventional urethral catheter.