PURPOSE: Recently, many alternative forms of non-surgical treatment modalities were devised for the management of BPH and one of them is transurethral radiofrequency thermotherapy(TURT). In this study, we investigated the long term efficacy of TURT. MATERIALS AND METHOD: A total of 132 patients with symptomatic BPH were treated in a single session with TURT using Thermex-ll(47.5 degrees C, 150minutes) and 88 patients who were available to follow-up for more than 6 months after TURT were enrolled in this study. Among them, 65 patients were available to follow-up for more than 2 years. The baseline and post-treatment mean symptom score(Madson-Iversen), maximal flow rate(MFR), residual urine volume and prostate volume were compared. Improvement was defined as a reduction of more than 50% in at least one of two parameters(symptom score and maximal flow rate). We also investigated whether other treatment modalities were selected in 2 years after TURT. RESULTS: At 3 months follow-up, improvements were observed in 59.1%(52/88), and at 6 months 54.5%(48/88). However, improvements in both symptom score and maximal flow rate at 3 and 6 months after treatment were only 27.3% and 20.5%, respectively. Among 65 patients who were available to follow-up for more than 2 years, 27 patients(41.5%) had undergone transurethral resection of the prostate either with(19) or without medication(8). 28 patients (43.1%) received medical therapy such as alpha blocker during the last two years after TURT. The post-treatment values of the 10 patients who had not received adjuvant therapy were not significantly different from those at baseline. CONCLUSIONS: Although thermal treatment for BPH is an alternative option with minimal complication in selected symptomatic patients who are not clear candidates for surgery or high-risk patients, the long term effect of TURT is not sufficient to relieve the obstructive and irritative symptoms of BPH.