This study aimed to examine moderated mediation effect of executive function and parental attitudes on the relationship between children’s effortful control and prosocial behavior in early schoold-age children. A questionnaire was administered to 300 parents with elementary school students first and second grade in korea. The moderated mediation model was analyzed using SPSS 23.0 and PROCESS macro 4.2. The main results are as follows. First, there were significant correlations among all major variables. Second, executive function was found to partially mediate the relationship between effortful control and prosocial behavior. Third, parenting attitudes in the autonomy and relatedness dimensions had significant moderating effects on the relationship between effortful control and executive function. Finally, a significant moderated mediation effect was confirmed, such that the indirect effect of effortful control on prosocial behavior via executive function varied depending on the levels of parental autonomy and relatedness. These findings suggest that children’s temperament and executive function combined with parenting environments, are crucial for promoting prosocial behavior during the transition to school.