Objective: The aim of this study was to to demonstrate the initial treatment outcomes of Greenlight (TM) potassium-titanyl- phosphate (KTP) laser on radiation-induced hemorrhagic cystitis. Background data: Hemorrhagic cystitis is a common complication of radiation therapy for pelvic tumors. Materials and methods: From September 2004 to February 2011, 10 patients with radiation-induced intractable hemorrhagic cystitis underwent transurethral Greenlight KTP laser coagulation of the bladder. The power setting was limited to 20-30 W. Results: Bleeding stopped in all cases after one session of laser treatment. Mean follow-up time was 17 months (6-36 months). All patients underwent cystoscopy 3 months postoperatively, and no bleeding or significant scar was found. Recurrence of significant bleeding was seen in one case 7 months post-operation, and was again cured by KTP laser. There were no complications from the procedures. Conclusions: Our experience suggests that transurethral coagulation using KTP laser is a safe and effective strategy for the treatment of hemorrhagic radiation cystitis.