Objective To explore the effect of Montelukast Sodium combined with Budesonide aerosol inhalation in the treatment of children with asthma.Methods A total of 86 cases of children with asthma treated in our hospital from August 2017 to December 2019 were selected as the research objects.The selected patients were divided into the observation group (n=43) and the control group (n=43) according to random number table method.The children in the control group were treated with Budesonide aerosol inhalation, and the children in the observation group were treated with Montelukast Sodium combined with Budesonide aerosol inhalation, the changes of clinical treatment effect, peak expiratory flow (PEF) and forced expiratory volume in the first second (FEV1) of the two groups were observed.Results After treatment, the FEV1 and PEF of the two groups of children were higher than those before treatment, the differences were statistically significant (P<0.05).The FEV1 and PEF in the observation group after treatment were higher than those in the control group, the differences were statistically significant (P<0.05).Through treatment, the total effective rate of children in the observation group was 95.35%, higher than the control group (81.40%), the difference was statistically significant (P<0.05).The total incidence of adverse reactions in the observation group was 2.33%, lower than the control group (13.95%), the difference was statistically significant (P<0.05).Conclusion Montelukast Sodium combined with Budesonide aerosol inhalation in the treatment of bronchial asthma has a significant effect, can significantly improve the lung function of children, clinical application value is high.