Based on the prosocial classroom model, this three-level meta-analysis synthesizes the associations between early childhood educators' (ECEs) social-emotional competence (SEC) and their well-being, teacher-student relationships, classroom management, social-emotional learning (SEL) implementation, student SEC, and organizational outcomes. Fifty-one studies with 511 effect sizes were included (N = 19,738). The results of random effect models revealed that ECEs' SEC was directly associated with positive well-being, close teacher-student relationships, effective classroom management, successful SEL implementation, and favorable organizational outcomes. These associations were largely invariant across teacher work experience, educational level, cultural background, and study design, although they were sporadically moderated by SEC components, teacher age, and quality of study. ECEs' SEC was not significantly related to students' overall SEC, but to students' social skills. Taken together, these findings support and advance the prosocial classroom model and highlight the importance of enhancing ECEs' SEC in fostering positive teacher, student, classroom, and organizational outcomes.