Objective: To study the impact of commercial health insurance on children's health and to propose targeted policy recommendations. Methods: A Probit model was used to study the impact of commercial health insurance on children's health，analyze the heterogeneity of children and household characteristics，and further test the mediating effects of children's medical expenditures and medical service utilization. Results: Commercial health insurance significantly promoted children's health，with more significant effects on children in agricultural households，high-income families，urban and central/western regions. The results of commercial health insurance improving children's health through medical expenditure and medical service utilization were not significant. Conclusion: Commercial health insurance can improve children's health，but its coverage rate is low. In this regard，China should accelerate the construction of a specialized medical insurance system for children at the national level and promote the effective interface between basic medical insurance and commercial health insurance for children.