Psychopathic traits in community and referred youths are strongly associated with severe externalizing problems and low prosocial behavior. However, less is known about the mechanisms that may link youth psychopathy and these outcomes. Social dominance orientation (SDO), defined as the general individual orientation toward unequal and dominant/subordinate relationships, might represent a valuable construct to explore to better understand the association between psychopathic traits, externalizing problems, and prosocial behavior. Based on this, the current study aimed to investigate the relationship between psychopathic traits, SDO, externalizing problems, and prosocial behavior in a community sample (N= 92, 45.57% females, mean age = 12.53, andSD= 0.60) and in a clinical (N= 29, 9% female, mean age = 12.57, andSD= 0.57) samples of adolescents with Oppositional Defiant Disorder or Conduct Disorder. Results showed that SDO mediated the relationship between psychopathic traits and externalizing problems and between psychopathic traits and prosocial behavior only in the clinical sample. These findings can provide valuable information on psychopathic trait correlates in youths with aggressive behavior disorders; treatment implications are discussed.