Objective: To investigate the effect of vitamin D assisted fluticasone propionate inhalation aerosol in the treatment of chronic asthma in children. Methods: 68 children with asthma who were treated in our hospital from April 2020 to February 2024 were selected as the study objects. According to random number table method, the children were divided into control group and observation group, with 34 cases in each group. The control group was treated with fluticasone propionate inhalation aerosol; Observation group was treated with vitamin D on the basis of control group. The clinical efficacy, laboratory indicators [25-hydroxyvitamin D3 (25- (OH)-D3), ECP, IgE] and lung function (FEV1, FVC, PEF) of the two groups were analyzed and compared. Results: The total effective rate of observation group was significantly higher than that of control group (P < 0.05). After treatment, the 25- (OH)-D3 level of the two groups was significantly higher than that of the control group, the ECP and IgE levels were significantly lower than before treatment, and the 25- (OH)-D3 level of the observation group was significantly higher than that of the control group, and the ECP and IgE levels were significantly lower than that of the control group (P < 0.05). After treatment, FEV1, FVC and PEF in 2 groups were significantly higher than those in control group, and FEV1, FVC and PEF in observation group were significantly higher than those in control group (P < 0.05). Conclusion: Combined with vitamin D, fluticasone propionate inhalation aerosol can improve the therapeutic effect, improve lung function, supplement vitamin D level and inhibit inflammation in children with bronchial asthma.