This study aimed to examine moderated mediation effect according to the task-focused behavior and teacher-child relationship on the influence of children’s executive function on play behavior type. The participants included 107 children(aged 4-5 years) and their mothers, and 72 teachers. Mediation(Model 4), moderation(Model 1), and moderated mediation (Model 15) models were analyzed using SPSS 25.0 and PROCESS macro 4.0 programs(Hayes, 2022). The study shows, first, task-focused behavior mediated the relationship between children's executive function and social play behavior. Second, the teacher-child intimacy moderated the effects of the children’s executive function on the social play, rough-tumble play, and reticent play. Third, the indirect effect of executive function through children’s task-focused behavior on rough-tumble play was moderated by teacher-child intimacy. These results suggest that the effect of the executive function on the play type through task-focused behavior is different according to the level of teacher-child intimacy. Therefore, the importance of the children’s executive function and teacher-child relationship that influences the level of participation of children in play behavior type was emphasized.