Abstract： Objectives： To observe the clinical effect of modified Xiaochaihu Decoction for postinfectious cough (PIC) in children with accumulation of pathogenic factors in shaoyang syndrome. Methods： A total of 120 cases of PIC children with accumulation of pathogenic factors in shaoyang syndrome were divided into the Xiaochaihu Decoction group and the western medicine group according to the random number table method ， with 60 cases in each group. The western medicine group was treated with routine western medicine，and the Xiaochaihu Decoction group was additionally treated with modified Xiaochaihu Decoction based on the treatment of the western medicine group. Clinical effects after 7 days of treatment were compared between the two groups. Traditional Chinese medicine syndrome scores，cough symptom scores， inflammatory responses， and immune function were compared before and after treatment between the two groups. Results： The total effective rate was 95.00% in the Xiaochaihu Decoction group， higher than that of 81.67% in the western medicine group (P＜0.05). After treatment， traditional Chinese medicine syndrome scores in the two groups were decreased (P＜0.05)，and the scores in the Xiaochaihu Decoction group were lower than those in the western medicine group (P＜0.05). After treatment，the scores of daytime cough and nighttime cough in the two groups were decreased (P＜0.05)， and the scores in the Xiaochaihu Decoction group were lower than those in the western medicine group (P＜ 0.05). After treatment，the levels of serum interleukin-6 (IL-6)，transforming growth factor- β1 (TGF-β1)， tumor necrosis factor-α(TNF-α)，and immunoglobulin E (IgE) in the two groups were decreased (P＜0.05)， and the above levels in the Xiaochaihu Decoction group were lower than those in the western medicine group (P＜0.05). Conclusion： For PIC children with accumulation of pathogenic factors in shaoyang syndrome， modified Xiaochaihu Decoction can improve curative effects， relieve clinical symptoms， reduce cough degree and body inflammatory responses， and enhance immune function， so as to effectively improve the condition.