This study aimed to investigate whether psychological wellbeing and self-differentiation have a double mediating effect on the relationship between childcare teachers’ mindfulness and job satisfaction. Accordingly, a random sampling method was employed to distribute questionnaires to 530 childcare teachers who worked in daycare centers in Seoul and Gyeonggi-do. After removing insincere responses, 489 questionnaires were analyzed. The results revealed that the higher the childcare teachers’ mindfulness, psychological wellbeing, and self-differentiation, the higher their job satisfaction. Furthermore, mindfulness leads to job satisfaction through self-differentiation and indirectly through psychological wellbeing. The mediating effect was confirmed as all indirect paths appeared to be significant. Moreover, it was demonstrated that the indirect path to job satisfaction through mindfulness sequentially through psychological wellbeing and self-differentiation was significant, thereby indicating that there was a double mediating effect. It is expected that this study’s results will be employed as basic data for the application of various individual and group counseling programs that may enhance childcare teachers’ psychological wellbeing and self-differentiation.