Objective. To evaluate efficacy and safety of WF10 (TCDO iv solution) therapy in patients with late hemorrhagic radiation cystitis and proctitis in a long-term follow up. Material and methods. From February 1999 to July 2001, 30 symptomatic patients with endoscopically confirmed grade 2 and 3 late hemorrhagic cystitis ( n = 16) and proctitis ( n = 14) were treated with WF10. The dose was 0.5 ml/kg BW, diluted in 250 ml 5%D/W, administered by intravenous infusion over 2 h, 5 consecutive days, every 3 weeks for 2–4 cycles, combined with standard therapy. The patients were clinically followed up every 3 weeks for 3 months, then every 3 months for 1 year and then every 3–6 months. The study endpoints were immediate response with improvement to Grade 0–1 within 3 months and the incidence of recurrence to Grade ≥2 during the follow up time. Results. After completion of the WF10 therapy, 14 cystitis patients (88%) had improved to grade 0–1 hematuria, and 14 proctitis patients (100%) had improved in bleeding per rectum to grade 0–1 within 3 months. The median follow up time was 51 months. During the follow up period, among the responders, 4 cystitis patients (28%) had recurrent hematuria of grade 2 and two proctitis patients (14%) had recurrent bleeding per rectum of grade 2 and 3. No treatment toxicity was observed. Conclusion. The WF10 therapy combined with conventional treatment is simple and safe with long-term efficacy in the treatment of late hemorrhagic radiation cystitis and proctitis.