Background There are limited studies comparing budesonide inhalation suspension (BIS) with montelukast in real-world settings where treatment adherence and persistency may be suboptimal.This real-world study aims to investigate the control effectiveness of montelukast or BIS as a monotherapy in Chinese children with mild asthma.Methods Data were derived from a retrospective questionnaire-based analysis of 2-14-year-old children with mild persistent asthma,who received either 500 μg of BIS (n =153) or 4-5 mg of montelukast (n =240) once daily.The indicators of asthma control,the Asthma Control Test (ACT)/Childhood ACT (C-ACT) score,and the asthma-related medical costs were assessed.The differences between the two groups were compared using an unpaired t-test (normally distributed),Mann-Whitney U test (non-normally distributed) or chi-squared test (categorical variables).Results Medication compliance in the past 3-month period was better in the montelukast group than in the BIS group(P =0.042).The montelukast group exhibited better asthma control in the past 4-week period,including lower percentages of asthmatic children with symptoms more than twice a week (P =0.021),had night waking or night coughing (P =0.022),or required reliever medication more than twice a week (P ≤ 0.001).The montelukast group had a lower percentage of children with an ACT/C-ACT score ≤ 19 (P=0.015).Caregivers reported a significantly better exercise tolerance in the children who received montelukast vs.BIS in the past 12 months (P ≤ 0.001).Significantly higher medical expenditures attributable to asthma in the past 12 months were observed in the BIS group vs.montelukast group (P ≤ 0.001).Conclusion Both treatments provided acceptable overall asthma control in children with mild persistent asthma;however,more reliever medication and more medical expenditures attributable to asthma were needed for BIS vs.montelukast in real-world settings,where factors such as compliance were also taken into account.