This study examines the effects of kindergarten teachers' self-efficacy on their perceived teacher-child relationships, and explores the associations between self-efficacy and two types of positive affective states (i.e., flow experience and psychological well-being) as the antecedents of efficacy beliefs. A sample of 796 kindergarten teachers in Hong Kong participated in this study. The results showed that teachers' flow experience and psychological well-being were significantly associated with their perceived positive teacher-child relationships, and teacher self-efficacy significantly mediated the effects of teachers' positive affective states on their perceived teacher-child relationships. The results highlight the significance of integrating social cognitive theory and positive psychology into the understanding of the relationships between teachers' positive affective states, self-efficacy, and teacher-child relationships in early childhood education settings. The implications for theory and practice are discussed. Copyright © 2022 Elsevier.