TUR-P for the treatment of BPH is not performed in cases with severe heart disease due to the risk of bleeding and hyponatremia etc. Besides, in cases with severe central nerve disease and dementia, TUR-P is not performed because patients cannot take postoperative rest. We report the efficacy and the safety of Photoselective Vaporization of the Prostate (PVP) using a high-power 80 W KTP (potassiumu-titayl-phosphate) in patients for whom TUR-P cannot be performed. 312 patients underwent PVP in our hospital. Of these 312 patients, 8 patients with severe heart disease (American Society of Anesthesiology score of 3 or greater) and 4 patients with severe dementia (Performance status of 3 or greater) were evaluated. We assessed peak flow rate and post-void residual urine volume preoperatively and at 3 months postoperatively, safety of the procedure, and complication rates. The mean age was 81 years old (range 67 to 94) and the mean prostate volume was 63.8 ml (range 19 to 120). Urethral catheter was used in 8 patients because of chronic urinary retention. PVP was performed with GreenLightPV and a saline solution was used for irrigation. Upon completion of the procedure an 18Fr Foley catheter was inserted without continuous bladder irrigation and removed next morning, as a rule. In all 12 patients, PVP was performed successfully without any intraoperative complications. Mean operating time was 101 minutes (range 28 to 184), mean total laser energy was 336,853 J (range 74,396 to 550,000), and mean irrigation volume was 21 L (range 8 to 36). The hemoglobin value changed from mean 13.1 mg/dl preoperatively to 12.2 mg/dl postoperatively. Blood transfusions were not required and hyponatremia was not observed. In 1 case, the urethral catheter was removed 3 hours following surgery. In the other cases, the urethral catheter was removed next morning. All patients could urinate after catheter removal and were discharged on the day following operation. Mean peak flow rate increased to 18 ml/s and mean post-void residual urine decreased to 46.9 ml at 3 months. No postoperative complications (urinary retention, hematuria, urinary tract infection, etc.) were observed. PVP is safe and effective in high-risk patients who are not candidates for TUR-P.