Objectives: This study aimed to examine the structural relationships among mothers’ smart media literacy, smart media mediation, young children’s overdependence on smart devices, and executive function.Methods: The Participants comprised 205 children aged 3 to 5 years old, and their mothers. The Early Years Toolbox (EYT) was used to measure young children’s executive function. The data obtained were analyzed using Cronbach’s α, frequency analysis, descriptive statistics, one-way ANOVA analysis, and partial correlation analysis with SPSS 25.0. Bootstrapping was used to examine the mediating effect while the Structural Equation Model (SEM) analysis was performed using AMOS 22.0.Results: First, young children’s executive function was positively associated with mothers’ smart media literacy and smart media mediation but negatively associated with young children’s overdependence on smart devices. Second, mothers’ smart media mediation and young children’s overdependence on smart devices sequentially mediated the relationship between mothers’ smart media literacy and young children’s executive function. It was also found that mothers’ smart media mediation partially mediated the relationship between mothers’ smart media literacy and young children’s executive function.Conclusion: These findings highlight the importance of mothers’ smart media literacy and smart media mediation for young children’s executive function and emphasize the need of prevention for overdependence on smart devices in facilitating executive function development in early childhood.