Background & aim: Aggression is a phenomenon that causes irreversible damage to a community. Psychodynamic theory suggests that aggression is rooted in early relationships with family members, especially mother. According to this theory, infant-mother relationship is a major predictor of an individual’s behavior from childhood to adulthood. This study aimed to investigate the correlation between mother-infant attachment styles and aggression. Methods: This study was conducted on 150 university students (75 female, 75 male) randomly selected from Bu-Ali Sina University in Hamadan, Iran. Data were collected via demographic questionnaires, Persian version of Adult Attachment Inventory (AAS) (Hazen and Shaver) and Ahvaz Aggression Inventory (AAI). Data analysis was performed using Pearson correlation and regression analysis. Results: According to our findings, secure mother-infant attachment had a significant negative correlation with aggression. In addition, ambivalent mother-infant attachment had a significant positive correlation with aggression, while avoidant attachment style had no significant correlation with aggression. Conclusion: According to the results of this study, secure attachment of mother with infant could reduce aggression during adulthood. On the other hand, ambivalent attachment between mother and infant could clearly increase the risk of aggression. Therefore, it is recommended to train different attachment styles to pregnant women through related workshops during pregnancy in order to prevent ambivalent mother-infant attachment.
