INTRODUCTION: Laser therapy has gained increasing acceptance as a relatively less invasive treatment for lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). From the early procedure of interstitial laser coagulation through to the use of holmium laser enucleation of the prostate, there has been an expanding body of evidence on the efficacy of such procedures. One of the newer lasers is the Green Light HPS 180 W laser. Studies with this GreenLight laser (GLL) (American Medical Systems, Inc, Minnetonka, MN, USA) showing results as good as those of transurethral resection of the prostate (TURP). In this paper, the efficacy of the new GLL 180-W versus the gold standard TURP in patients with LUTS due to BPH was tested in a prospective clinical trial. OBJECTIVE: To compare results of Green light laser (GLL) evaporisation of the prostatae and transurethral resection of the prostate (TURP) for treatment of BPH. MATERIJALS AND METHODS: A total of 62 patients with BPH were randomly assigned to two equal groups: TURP or GLL. RESULTS: Both groups were compared regarding all relevant preoperative, operative, and postoperative parameters. Functional results in terms of improvement of International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), and postvoid residual (PVR) urine were assessed at 1, 3, 6 and 12 mo. A total of 62 patients completed 12 mo of follow-up in the TURP and GLL groups, respectively. Baseline characteristics were comparable. Mean operative time was significantly shorter for TURP. Compared to preoperative values, there was significant reduction in hemoglobin levels at the end of TURP only. A significant difference in favor of GLL was achieved regarding the duration of catheterization and hospital stay. In the GLL, no major intraoperative complications were recorded and none of the patients required blood transfusion. Among TURP patients, 6 required transfusion, 1 developed TUR syndrome, and capsule perforation was observed in 5 patients. There was dramatic improvement in Qmax, IPSS, and GLL compared with preoperative values and the degree of improvement was comparable in both groups at all time points of follow-up. Four TURP patients and one GLL patients developed bladder neck contracture treated by bladder neck incision; none in either group experienced urethral stricture or urinary incontinence. CONCLUSIONS: Compared to transurethral resection of the prostate, GreenLight HPS 180-W laser photoselective vaporization of the prostate is safe and effective in the treatment of patients suffering from lower urinary tract symptoms due to benign prostatic hyperplasia.