To study the effect of modified Wuhu Decoction on children with mycoplasma pneumonia of phlegm-heat obstructing lungs and the changes of T-lymphocyte subsets (CD3+、CD4+、CD8+、CD4+/CD8+)．Methods:A total of 60 cases of children with mycoplasma pneumonia of phlegm-heat obstructing lungs admitted to the First Affiliated Hospital to Guangzhou University of Chinese Medicine were randomly divided into an observation group and a control group.The control group were treated with azithromycin (Zithromax)and the observation group were treated with modified Wuhu Decoction and azithromycin.Symptom Integral score,the level of T-lymphocyte subsets (CD3+、CD4+、CD8+、CD4+/CD8+）before and after treatment were compared.Results:There was no significant difference in the clinical control rate,control display rate,and total effective rate between the 2 groups (P>0.05).The scores,symptom scores,fever time,cough time,and lung rales duration after treatment in the 2 groups were improved compared with those before treatment,and the difference was statistically significant (P<0.01),and the observation group was superior to the control group.There was a significant difference in CD8+ and CD4+/CD8+ between the 2 groups (P<0.01).Conclusion:Azithromycin combined with modifed Wuhu Decoction was effective in the treatment of children with MMP.In improving the clinical symptoms and signs,especially in improving clinical symptoms and signs,it is better than the azithromycin group alone.It may be related to the regulation of T lymphocyte and the reduction of pulmonary immune inflammatory response.