Abstract：Objective：To observe the clinical effect of Yangyin Qingfei tang for prevention and treatment of acute radiation induced oral mucositis after radiotherapy for nasopharyngeal carcinoma. Methods： A total of 72 cases of patients received radiotherapy for nasopharyngeal carcinoma were divided into the control group and the observation group according to the random number table method， 36 cases in each group. Both groups were given intensity- modulated radiotherapy； the control group was given routine oral nursing， and the observation group was additionally given the oral administration of Yangyin Qingfei tang based on the treatment of the control group. After radiotherapy， the occurrence， severity and mean appearance time of acute radiation induced oral mucositis in the two groups were compared；the levels of C-reactive protein (CRP)， transforming growth factor- β1(TGF- β1) and tumor necrosis factor- α(TNF- α) in serum in the two groups were detected and compared. Results： The incidence of acute radiation induced oral mucositis higher than Ⅱ degree in the observation group was lower than that in the control group， and the mean appearance time of oral mucositis was later， differences being significant(P＜0.05). Before radiotherapy，there was no significant difference being found in the comparison of the levels of CRP，TGF-β1 and TNF-α in serum between the two groups(P＞0.05)；after radiotherapy，the above levels in the two groups were increased when compared with those before radiotherapy，but the increase in the observation group was lower than that in the control group， differences being significant(P＜0.05). Conclusion： During radiotherapy， the simultaneous treatment of Yangyin Qingfei tang for patients with nasopharyngeal carcinoma can effectively delay the occurrence of acute radiation induced oral mucositis， reduce the severity of lesions， and improve the tolerance degree of radiotherapy.