Abstract: Objective: To evaluate the preliminary clinical results of tomotherapy for 45 nasopharyngeal carcinoma（NPC） patients. Methods: Between September 2007 and September 2008,45 newly diagnosed NPC patients were treated with tomotherapy at the dose of 70-76Gy/32-33F for the gross tumor volume（pGTVnx） and positive lymph nodes（GTVnd）,and 60-66Gy/32-33F for the high risk clinical target volume（CTV1）,and 49.5-56.1Gy/32-33F for the low risk clinical target volume（CTV2）,respectively.Acute lesions were evaluated with the RTOG/EORTC criteria. Results: The median follow-up time was 6 months.The grades 1-3 of acute toxicity to skin were 75.6%,17.8% and 2.2%,respectively.The grades 1-2 and 3 of acute toxicity to mucous membrane of mouth were 97.8% and 2.2%,respectively.The grades 1 and 2 of acute toxicity to xerostomia were 48.9% and 46.7%,respectively.None of grade 3 acute toxicity was detected.The remission rate of primary lesion and positive lymph nodes was 88.9% and 90.0%,respectively.No PD or local recurrence was detected. Conclusion: NPC TomoTherapy has a low incidence of severe acute toxicity and a short therapeutic time.