To study the therapeutic effect of Jiawei Diyu Powder（加味地榆散）on lung cancer targeted therapy in patients with oral mucositis of Yin deficiency and heat toxin syndrome.

86 patients with lung cancer targeted therapy for oral mucositis with Yin deficiency and heat toxin syndrome were randomly divided into two groups according to the order of treatment.There were 43 cases in each group.The patients in the control group were treated with Compound Chlorhexidine Gargle and oral administration of vitamin B₂ and vitamin C，and those in the observation group were treated with Jiawei Diyu Powder on the basis of the control group.The oral mucositis grading，TCM symptom scores（dry mouth and throat，sore mouth and tongue，swollen gums and pain，hand-foot-heart heat），inflammatory factor levels［serum interleukin-6（IL-6），interleukin-8（IL-8）and tumor necrosis factor（TNF-α）］，Karnofsky performance score（KPS）and adverse reactions（abnormal taste，yellow tongue coating，nausea and vomiting，belching，etc.）were compared between the two groups.

There was no significant difference in the classification of oral mucositis between the two groups before treatment（P>0.05）.After treatment，the observation group was significantly better than the control group（P<0.05）.After treatment，the above scores of the two groups were significantly decreased（P<0.05），and the scores of TCM symptoms in the observation group were significantly lower than those in the control group（P<0.05）.There was no significant difference in serum IL-6，IL-8 or TNF-αbetween the two groups before treatment（P>0.05）.After treatment，the levels of inflammatory factors in the two groups were significantly decreased（P<0.05），and the levels of the observation group were significantly lower than those of the control group（P<0.05）.After treatment，the KPS scores of the two groups were significantly increased，and the score of the observation group was significantly higher than that of the control group（P<0.05）.The incidence of adverse reactions in the observation group and the control group was 9.30%（4/43）and 6.98%（3/43），respectively，and the difference was not statistically significant（P>0.05）.

Jiawei Diyu Powder has a satisfactory therapeutic effect on patients with lung cancer targeted treatment of oral mucositis with Yin deficiency and heat toxin syndrome.It can significantly improve the classification of oral mucositis，eliminate the inflammation，relieve various discomfort symptoms，and improve the health level of the body.It is a safe and effective medication regimen.