Abstract: Objective :To evaluate the clinical efficacy,thermal enhancement ratio,and toxicity of intracavitory thermotherapy with radiotherapy for patients with nasophaiyngeal carcinoma. Methods : Seventy untreated patients with nasopharyngeal carcinoma were divided into the combined group (intracavitaiy theimotheiapy plus radiotherapy) and the controlled group (radiotherapy alone) based on treatmental methods. The combined group was given intiacavitaiy hyperthermia with a 915MHz microwave hyperthemia unit. The surface temperature of nasopharyngeal tumor ranged from 42% to 43%. The warm-up time was 40 minutes, once or twice per week, 4 weeks in all. Radiotherapy was performed by 6MYX and 10MEVβ. The total dose for primary nasopharyngeal tumor and cervical metastatic cancer was 70 to 80Gy and 60 to 70Gy, respectively. A fractionated dose of 2Gy/fraction/day was delivered, with five fractions/ week. Results :The total remission rate for primary nasopharyngeal tumor in thermotherapy group and radiotherapy group was 65.7% and 31.4% and the effective rate was 97.1% and 77.1%, respectively. There was a significant difference in the comparion between the two; the total remission rate for cervical metastatic cancer was 87.5% and 81.8% and the effective rate was 100.0% and 100.0%, respectively. There was no statistical significance in the comparion. The thermal enhancement ratio of half shrink and disappearance of nasopharyngeal tumor was 1.68 and 1.39. Conclusions :Intracavitary thermotherapy plus radiotherapy is better than radiotherapy alone.