Background: Nowadays, modern technology and various applications have been indispensable parts in family daily lives and children’s development, parental phubbing and preschool children’ electronic media use have been a common phenomenon. Objective: To clarify the relationship between maternal phubbing and preschool children’s problem behaviors, as well as its potential underlying mechanisms, the current study examined the association between maternal phubbing and problem behaviors, as well as mediating role of preschool children’s electronic media overuse, and the moderating role of secure attachment. Participants and Setting: In total, 460 mothers with preschool children were recruited to complete a battery of questionnaires . All questionnaires required mothers to provide truthful and detailed responses based on their own behaviors, experiences, and observations of their children’s behaviors and media use. Methods: Linear regression analysis was used to examine the predictive effect of maternal phubbing on preschool children’s problem behaviors, as well as the mediating role of electronic media overuse and the moderating role of secure attachment. Results: (1) Maternal phubbing was positively associated with preschool children’s problem behaviors, preschool children’s electronic media overuse could significantly mediate this relation. (2) The mediating effect of electronic media overuse was moderated by secure attachment, and both the two mediating pathways were more significant for preschool children with lower level of secure attachment. Conclusions: Maternal phubbing and preschool children’s electronic media overuse were both found to be positive predictors of preschool children’s problem behaviors. Moreover, maternal phubbing could indirectly promote the occurrence of children’s problem behaviors through their electronic media overuse. Although secure attachment can serve as a protective factor against risk factors, its protective effect is limited-it only buffers the two pathways of the mediating effect.