Objectives To compare the characteristics of tidal breathing lung function in infants with wheezing and non-wheezing pneumonia. Methods We retrospectively compared 86 infants with wheezing pneumonia (wheezing group) and 27 infants with non-wheezing pneumonia (control group), whose tidal breathing lung function and bronchodilator tests were performed after admission. Demographic and clinical data, differences in tidal breathing lung function and bronchodilator test, and correlations between clinical data and tidal breathing lung function indicators were analysed. Results Compared to the control group, it was significant higher in both the level of PTEF/TEF25 of tidal breathing lung function (162.4 vs 143.3, P=0.037)and the positive rate of abnormal airway obstruction(23.3% vs 44.4%, P=0.033) in the wheezing group. After bronchodilator test, the positive remission rates of TEF50/TIF50 and TEF50 was significantly higher in the wheezing group(53.5% vs 29.6%, P=0.03 and 58.1% vs 33.3%, P=0.024, respectively). Besides, RR, VT, PEF, and TEF25, TEF50, TEF75 of tidal breathing lung function were closely correlations to infants’ age, height, weight, and platelet counts in both wheezing and control groups. Conclusion Airway obstruction was very serious in infants’ wheezing pneumonia which can be partially improved by nebulisation with bronchodilator. Tidal breathing lung function was helpful for understanding the condition of airway, and monitoring disease progression in children with lung disease particularly in wheezing pneumonia.