To investigate the clinical effect and mechanism of Xiaoer Baotaikang Granules combined with oseltamivir phosphate in the treatment of influenza A with wind-heat invading defensive qi.Methods:A total of 70 children with influenza A positive and syndrome of wind-heat invading defensive qi treated in the Department of Pediatrics of Wuhan Hospital of Traditional Chinese Medicine from October 2021 to July 2022 were selected and divided into an observation group and a control group by random number table,with 35 cases in each group.The control group was given basic treatment,mainly antipyretics and rehydration,combined with oral administration of oseltamivir phosphate granules.The observation group was treated with Xiaoer Baotaikang Granules on the basis of the control group.After 5 days of treatment,the time of fever,catarrhal symptoms and cough disappearance were observed and recorded,and the curative effect was evaluated.Additionally,the levels of inflammatory factors high-sensitivity C-reactive protein(hs-CRP),procalcitonin(PCT),and interleukin-6(IL-6) were tested on the 1st and 5th day after admission,and the occurrence of adverse reactions in the two groups was observed.Finally,SPSS 26.0 was used for data analysis to compare the difference between the two groups.Results:The total effective rate of the observation group was 97.14%,higher than 85.71% of the control group(P<0.01).The time of fever,catarrhal symptoms and cough disappearance in the observation group were shorter than those in the control group(all P<0.05).After treatment,the levels of hs-CRP,PCT and IL-6 in the two groups were decreased compared with the conditions before treatment,and the levels in the observation group were lower than those in the control group(all P<0.05).Conclusion:Xiaoer Baotaikang Granules combined with oseltamivir phosphate could significantly accelerate the time of fever disappearance,shorten the course of disease,improve fever,cough,abdominal distension and other symptoms,and reduce the levels of inflammatory factors in children with influenza A and wind-heat invading defensive qi,showing good clinical efficacy and without obvious adverse reactions.Its mechanism might be related to the regulation of internal heat source and the inhibition of inflammatory factor secretion.