Fearful inhibition and impulsivity-anger significantly predict internalizing and externalizing problems, respectively. An important moderator that may affect these associations is frontal EEG asymmetry (FA). We examined how temperament and FA at 6 years interactively predicted behavioral problems at 9 years. A community sample of 186 children (93 boys, 93 girls) participated in the study. Results indicated that the effect of fearful inhibition on parent-reported internalizing problems increased as children exhibited greater right FA. The effect of impulsivity-anger on parent-reported externalizing problems increased as children showed greater left FA. Because FA was allowed to vary rather than children being dichotomized into membership in left FA and right FA groups, we observed that children’s FA contributed to the resilience process only when FA reached specific asymmetry levels. These findings highlight the importance of considering the different functions of FA in combination with specific dimensions of temperament in predicting children’s socioemotional outcomes. Clinical implications include providing suggestions for intervention services by demonstrating the role of FA in developing behavioral problems and inspiring research on whether it is possible to alter EEG activation and thus potentially improve developmental outcomes.