Background and purpose: Due to the increasing number of orphans and their maladaptive behaviors and emotional disorders, it is necessary to pay special attention to this population. Present study aimed to compare the aggression and emotional knowledge between orphanage and abandoned children with normal children.

Method: The present study was a causal-comparative research. The sample consisted of 64 male children aged four to six years old (32 orphans and abandoned children and 32 non-orphans), who were selected using convenience sampling method and were assessed using Preschool Aggression Questionnaire (Vahedi et al, 2008) and emotional matching task (Izard et al, 2003). Data were analyzed using independent sample t-test and MANOVA.

Results: Result of independent sample t-test showed significantly higher levels of aggression in orphans and abandoned children comparing to non-orphans (p= 0/0001). Moreover, orphans and abandoned children showed significantly lower emotional knowledge comparing to non-orphans (p= 0/0001). In addition, results of MANOVA revealed that orphans and abandoned children had significantly lower scores in components of emotional knowledge (p < .05).

Conclusion: Present study showed that children’s aggression and emotional knowledge is mainly influenced by parents’ parenting styles.