Objective To evaluate the efficacy and safety of 140W greenlight laser high performance system (HPS) for photoselective vaporization of prostate (PVP) procedure in the treatment of lower urinary tract obstruction secondary to prostate cancer. Methods A total of 65 senile prostate cancer patients suffering from lower urinary tract obstruction who were admitted in our department and treated with greenlight laser HPS from August 2009 to February 2012 were enrolled in this study. Their operation manipulation time, peri-operative bleeding, post-operative catheterization time, complications, International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), and the change in prostate volume before and after treatment were recorded. Results All procedures were completed successfully in the cohort. The operation time ranged from 50 to 110 (68.9±23.9)min, the peri-operative bleeding amount from 50 to 140 (74.9±22.4)ml, and hospitalization time from 5 to 7d. No permanent urinary incontinence was found. Qmax was increased from (4.98±2.15)ml/s to (15.31±3.36)ml/s at 1 month after operation, the volume of the prostate was decreased from (72.3±13.9)g to (35.4±6.8)g, and the IPSS score was decreased from (22.15±3.41) to (6.02±2.01). Significant difference was found in all above indices before and after surgery (P＜0.01). Conclusion Greenlight laser HPS PVP procedure is a better approach for lower urinary tract obstruction secondary to prostate cancer because of its small amount of blood loss, rapid postoperative recovery and lower incidence of complications.