This paper reports preliminary results with intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma (NPC). Between August 2000 and May 2001, we treated 19 patients with NPC using IMRT. Twelve patients had stage I-II disease and seven had stage III-IV disease. Six patients received 9.0-19.8 Gy three-dimensional conformal radiotherapy (3D-CRT) before IMRT and 18 patients received a brachytherapy boost after IMRT. The mean follow-up time was 13.0 months. All patients with stage II-IV disease except one received two cycles of chemoradiotherapy with cisplatin and 5-fluorouracil (5-FU) during radiotherapy, followed by two to four cycles of chemotherapy after radiotherapy. Tumor response was assessed using clinical examination and computerized tomography or magnetic resonance imaging. The mean doses administered to the gross tumor volume and clinical tumor volume were 70.9 Gy and 63.2 Gy, respectively. The mean doses administered to the right and left parotid glands were 38.1 Gy and 38.6 Gy, respectively. All 19 patients had a complete response of primary and lymph node disease. Grade III mucositis developed during chemoradiotherapy in 15 patients (79%). In addition, clinical grade I xerostomia was recorded in nine patients, grade II in nine, and grade III in one. This study demonstrated that 3D-CRT, IMRT, intracavitary brachytherapy, and chemotherapy are effective and safe methods to treat NPC. Although IMRT treatment spared parotid gland function, its efficacy may be significantly influenced by disease stage and location of the neck lymph nodes. More cases and a longer follow-up to assess survival and complications are planned.