Objective To explore the changes and the clinical significance of tidal breathing lung function in infants with recurrent wheezing after bronchiolitis in Cangzhou rural area. Methods One hundred and two infants with recurrent wheezing after bronchiolitis were enrolled.According to asthma predictive index,the infants were divided into positive group (n=45) and negative group (n=57) as observation group,and another 30 healthy children were enrolled as control group.Tidal breathing lung function of acute stage (on admission),remission stage and recovery stage (3 months after discharge from hospital) were tested,the ratio of time taken to reach peak expiratory flow to total expiratory time( TPTEF/TE) and the ratio of peak expiratory volume to total expiratory volume( VPEF/VE) were compared among three groups. Results In acute stage,TPTEF/TE,VPEF/VE,VT,Ti,Te showed no significant statistical differences (P>0.05) between positive group and negative group,but TPTEF/TE and VPEF/VE were significantly decreased,compared with control group (P<0.01).In remission stage,TPTEF/TE,VPEF/VE in positive group and negative group were higher than those in acute stage,but significantly lower than those in control group (P<0.05).In recovery stage,TPTEF/TE,VPEF/VE in positive group were lower than those in control group (P<0.01).While the difference between negative group and control group showed no statistical significance (P>0.05). Conclusions Among the infants with recurrent wheezing after bronchiolitis in Cangzhou rural area,the lung function damage duration is longer in asthma predictive index positive group than in the negative group,and still existed 3 months after discharge from hospital.Tidal breathing lung function test can provide some clinical reference for early recognition of asthma and can be helpful in developing standard treatment plans for the prevention and treatment of asthma.