Objective To investigate the effect of 15% azelaic acid gel on lesion count, acne severity and quality of life in children with mild to moderate acne. Methods A total of 80 children with mild to moderate acne treated in the Outpatient Department of Yuyue Town Health Center of Deqing County from January 2024 to December 2025 were selected, and they were divided into the control group and the observation group by the random number table method, with 40 children in each group. The control group was treated with topical 2.5% benzoyl peroxide gel, and the observation group was treated with topical 15% azelaic acid gel. The lesion count, acne severity, quality of life, clinical efffcacy and adverse reaction rate were compared between the two groups. Results After 8 weeks of treatment, the counts of non-inffammatory lesions, inffammatory lesions and total lesions, as well as GAGS and CDLQI scores in the two groups were lower than those before treatment, and those in the observation group were lower than those in the control group (P<0.05). The total clinical effective rate of the observation group (92.50%) was higher than that of the control group (75.00%), and the incidence of adverse reactions (12.50%) was lower than that of the control group (32.50%) (P<0.05). Conclusion 15% azelaic acid gel can reduce skin lesions in children with mild to moderate acne, alleviate acne severity, and improve quality of life, with favorable local safety.