Parent-reported reactions to children’s negative emotions and child negative emotionality were investigated as correlates of internalizing and externalizing behaviors. Children (N = 107) and their parents participated in a short-term longitudinal study of social development. Mothers and fathers independently completed questionnaires assessing parental reactions to their child’s negative emotions and child negative emotionality at Time 1 (33 months) and child behavior problems at Time 2 (39 months). Child negative emotionality was significantly related to greater internalizing and externalizing behavior. Maternal and paternal punitive reactions were related to greater internalizing behavior, but only for boys with high levels of negative emotionality. Results indicate that child temperament and child gender may be important moderators of the relation between parental emotion socialization and child internalizing problems during the toddler and early preschool years.