Early childhood educator's emotional socialization may contribute crucially to young children's social-emotional competence. Here, we examined the contributions of self-reported reactions to children's emotions and beliefs about emotional socialization of 90 teachers to the social-emotional competence of 334 pre-schoolers. Teacher-reported emotion socialization, especially as moderated by classroom socioeconomic risk, often predicted pre-schoolers' end-of-year social-emotional behaviours, independent of child covariates, including children's beginning-of-year premeasures. Only three findings resembled the parent emotion socialization literature, however, and two appeared unique to the pre-school environment. Most were specific to classrooms where children experienced socioeconomic risk. The pattern of moderation findings highlights the importance of context in teachers' emotional socialization. Suggestions are given for expanded research on the topic and potential applications to assist teachers in their role as emotion socializers.