The main purpose of this study was to reveal the preschool teachers' composite structure of psychological capital (PsyCap), and potential association between adult preschool teachers' PsyCap and job performance. 389 preschool teachers were assessed with self-efficacy, state hope, optimism, resilience and job performance scale. The obtained data were analyzed by covariance-based structural equation modeling and component-based structural equation modeling. The results showed that structure of preschool teachers' PsyCap was composed of self-efficacy, state hope, optimism, resilience, and there was significantly potential association between adult preschool teachers' PsyCap and job performance. Based on the findings, suggestions for future studies are provided.