This study examined the linkages between parental discipline practices, peer relationships, and antisocial behavior in a 2-yr longitudinal study ( N = 206) of preadolescent boys (aged 9-10 yrs at 1st assessment). Structural equation models were used to estimate the stability of parenting, peer relations, and antisocial constructs, and their effects on each other. The results showed that preadolescent antisocial behavior had substantial concurrent negative effects on the quality of parental discipline and peer relationships. Evidence for a reciprocal relationship between parental discipline and child antisocial behavior was found. The study specifies how parental discipline practices are involved in maintaining the stability of antisocial behavior in preadolescents. Low popularity with peers did not directly influence the child’s antisocial behavior.