Objective To study the effect of intermittent versus daily inhalation of budesonide on pulmonary function and fractional exhaled nitric oxide (FeNO) in children with mild persistent asthma. Methods A total of 120 children, aged 6-14 years, with mild persistent asthma who attended the hospital from January 2016 to January 2018 were enrolled. The children were divided into an intermittent inhalation group with 60 children (inhalation of budesonide 200?μg/day for 6 weeks when symptoms of asthma appeared) and a daily inhalation group with 60 children (continuous inhalation of budesonide 200 μg/day) by stratified randomization. The children were followed up at months 3, 6, 9, and 12 of treatment. The two groups were compared in terms of baseline data, changes in FeNO and pulmonary function parameters, amount of glucocorticoid used, number of asthma attacks, and asthma control. Results At the start of treatment, there were no significant differences in baseline data, FeNO, and pulmonary function between the two groups (P > 0.05). Over the time of treatment, FeNO gradually decreased and pulmonary function parameters were gradually improved in both groups (P < 0.001). Compared with the intermittent inhalation group, the daily inhalation group had a better effect in reducing FeNO and increasing the predicted percentage of forced expiratory volume in 1 second (FEV1%pred) (P < 0.001). The inhalation method and treatment time had an interaction effect on FeNO and pulmonary function parameters (P < 0.001). In the daily inhalation group, FeNO and lung function parameters were improved rapidly and stabilized after 3 months of treatment, while those in the intermittent inhalation group stabilized after 6 months. After 12 months of treatment, there were no significant differences in the increases in body height and body weight and the degree of disease control between the two groups (P > 0.05). Compared with the daily inhalation group, the intermittent inhalation group had a significantly lower amount of budesonide inhaled (P < 0.05) and a significantly higher number of asthma attacks (P < 0.05). Conclusions Intermittent inhalation and daily inhalation of budesonide can achieve the same level of asthma control in children with mild persistent asthma and both have no influence on the increases in body height and body weight. Daily inhalation of budesonide can produce a better efficiency in reduing FeNO and increasing FEV1%pred. Although intermittent inhalation can reduce the amount of glucocorticoid used, it may lead to a higher risk of asthma attacks.