This study examined the moderating effect of preschoolers’ effortful control temperament and parenting attitude on the process of preschoolers behavioral inhibition temperament affecting mastery motivation. For this purpose, 233 parents of children aged 36 to 60 months, 117 boys (50.2%) and 116 girls (49.8%), were surveyed. Preschoolers’ behavioral inhibition temperament, effortful control temperament, mastery motivation, and parenting attitude were measured. The hypotheses were tested using the PROCESS macro for moderated moderation analysis. Results showed a significant three-way interaction between preschoolers’ behavioral inhibition temperament, effortful control temperament, and parenting attitude. Alternatively, these results suggest that effortful control temperament and parenting attitude can change the influence of the behavioral inhibition temperament on preschoolers’ mastery motivation. Based on these results, it has been suggested that it is important for parents to provide a consistent and stable "structure" for the improvement of children's motivation and achievement, so it is meaningful to help use effective parental education by providing information necessary for educational or counseling scenes.