The purpose of this study is to examine the influence of the child care teacher’s ego-resiliency and social interest on work engagement focusing of the mediation effect of social interest. The subjects were 285 childcare center teachers in A Province. Questionnaires, which required a self-report by the childcare center teachers, were used to investigate ego-resiliency, Adlers’ social interest, and work engagement. The collected data were analyzed by structural equation modeling (SEM), bootstrapping, and Pearson correlation using AMOS 10.0 and SPSS 21.0. The results of our study are as follows. First, SEM revealed that the social interest partially mediated the relationship between ego-resiliency and work engagement. Second, the childcare center teacher’s ego-resiliency influenced social interest. Third, the childcare center teacher’s ego-resiliency and social interest directly influenced work engagement. Fourth, childcare center teacher’s ego-resiliency indirectly influenced work engagement by social interest. The results of this study can be used to promote the childcare center teacher’s work engagement through social interest.