Parental emotion socialization (ES) facilitates emotion regulation (ER) in youth, and in turn, impacts risk for psychopathology from childhood through adulthood. While these links are well-documented, self-criticism has received limited attention in relation to ES or ER, despite its transdiagnostic nature. Moreover, no studies have examined how mindfulness may serve to moderate the association between unsupportive ES and ER. Structural equation modeling was used to explore relationships among recalled ES (happiness and sadness) and current ER, self-criticism, and mindfulness in a sample of emerging adults. Final model fit was good across all four models. Supportive ES (happiness and sadness) and unsupportive ES (sadness) predicted self-criticism in the expected directions. ES predicted ER in happiness and sadness models. Specifically, supportive and unsupportive ES predicted expressive suppression, and supportive ES predicted cognitive reappraisal. ES was indirectly associated with self-criticism through ER. Mindfulness did not moderate the link between unsupportive ES and ER.