A total of 903 patients (non-UR 732 patients; AUR 135 patients; CUR 36 patients) with a mean age of 68.8(± 6.4) years were identified. For temporary relief of AUR, CIC was adopted in 70.4% of the patients, urethral catheter indwelling in 22.2%, and urethral catheter indwelling followed by CIC in 7.4%. Mean duration of CIC was 2.2 (± 6.6) days and that of urethral catheter indwelling was 5.1 (± 16.6) days. For temporary relief of CUR, CIC was adopted in 33.3%, urethral catheter indwelling in 25.0%, and urethral catheter indwelling followed by CIC in 2.8%. The mean duration of CIC was 13.2 (± 38.0) days and that of urethral catheter indwelling was 3.5 (± 10.0) days (P<0.001). Mean baseline Qmax in non-UR, AUR and CUR group was 7.6 ml/s, 6.6 ml/s and 4.8ml/s, respectively (P<0.001); Mean total prostate volume was 66.1 (± 31.5), 89.9(± 44.8), 85.3 (± 38.1)ml (P< 0.001). Urodynamic detrusor underactivity was found in 28 (3.8%) of the non-UR patients, 11 (8.1%) of the AUR patients, and 2 (5.6%) of the CUR patients (P=0.082). Mean PdetQmax were 64.4, 74.3 and 77.7cmH2O (P<0.001); mean BOO index were 49.5, 61.1 and 69.4 (P<0.001); mean operation time were 54.0, 68.5, and 68.7 mins (P<0.001); mean enucleation weight were 20.7, 35.0 and 34.1 grams (p<0.001), respectively. There was no difference in intraoperative complication such as bladder injury, prostatic capsule perforation, or persistent bleeding. Necessity for additional continuous bladder irrigation was more frequent in AUR patients (p<0.001) than other groups during immediate postoperative period. There was no difference in mid-term postoperative complication such as delayed bleeding, stress urinary incontinence, urethral stricture, or bladder neck contracture up to 6 months followup. Postoperatively, IPSS, OABSS, and Qmax were improved in all three groups and there was no difference among the three groups. Mean PVR just before surgery in non-UR, AUR and CUR group was 55 ml, 75 ml and 333 ml, respectively, and its difference still remained significant among the three groups (15ml, 22 ml and 52 ml, respectively) at postoperative 6 months (P<0.001). None in both AUR and CUR group required CIC or urethral catheter at postoperative 6 months