The present study examines the relation between knowledge of emotion regulation strategies and social behavior in preschoolers. Knowledge of emotion regulation strategies of 210 children (mean age 55 months) was assessed. Teachers rated children’s social behavior with SDQ. Linear regression analysis examined how knowledge of emotion regulation strategies influenced social behavior of children. Significant effects of gender on SDQ scales ‘prosocial behavior’, ‘hyperactivity’, ‘behavior problems’, and SDQ total problem scale were identified. Age was a significant predictor of SDQ scales ‘prosocial behavior’, ‘hyperactivity’, ‘problems with peers’ and SDQ total problem scale. Knowledge of emotion regulation strategies predicted SDQ total problem scores. Results suggest that deficits in knowledge of emotion regulation strategies are linked with increased problem behavior.