This study aimed to examine the impact of child caregivers’ positive psychological capital on service quality, as well as the mediating effect of job identity on their relationship. Specifically, it investigated how caregivers’ positive psychological capital is reflected in job identity and clarified the pathway leading to service quality. A total of 278 child caregivers participated in the study. Data were analyzed using SPSS, including descriptive statistics, correlation analysis, and Model 4 of the Process macro to verify the mediating effect. The main findings were as follows. First, caregivers’ positive psychological capital directly influenced service quality. Second, job identity mediated the relationship between positive psychological and service quality. These results suggest that to improve service quality, it is important to strengthen both the job identity and positive psychological capital of child caregivers. This study provides baseline data for designing training programs and continuing education aimed at enhancing child care services.