Objective: This study aimed to investigate the influence of the moderated mediating effect of mentalization by self-esteem on the relationship between attachment to parents and anger regulation among college students. Methods: This study included 389 college students (229: 58.9% female and 160: 41.1% male, Mage = 21.19, SE = 2.04). The participants completed self-report questionnaires designed to assess attachment to their parents, mentalization, self-esteem, and anger regulation. Data were analyzed for moderated mediating effects between variables using PROCESS macro models 1, 4, 14. Results: First, mentalization fully mediated the relationship between parental attachment and anger regulation. This is the more stable the attachment formed with parents, the more the mentalizing ability developed, which improved anger regulation. Second, self-esteem moderated the relationship between mentalization and anger regulation. Even when self-esteem was low, mentalization effected on anger regulation. However, as self-esteem increased, the effect of mentalization on anger regulation increased. Finally, self-esteem moderated the mediating effects of mentalization on the relationship between parental attachment and anger regulation. This means that the higher the self-esteem, the greater the mediating effect of mentalization between attachment to the parent and anger regulation. Conclusions: This study provides academic and practical information by understanding the importance of parental attachment, mentalization, and self-esteem, and confirms that these factors serve as protective factors for anger regulation.