The present study examined child and maternal predictors of children's social competence in preschool. One hundred ten mothers and their preschool-aged children participated. Mothers completed parent reports of child temperament and self-regulation, and self-reports of maternal separation anxiety. Mothers' interactional style was coded from videotapes during preschool. Teachers rated children's social competence at the end of the first semester of school. Child age, temperament and self-regulation, and maternal characteristics predicted children's social competence. The interaction of anger proneness and self-regulation predicted both externalizing and prosocial behavior. Finally, children with greater risk factors were lower on prosocial behavior and higher on externalizing behavior than children with fewer risk factors. Results indicate that maternal and child characteristics may be used to identify children at risk for lower social competence in preschool, such that interventions may be implemented.