This study examined the factors influencing the psychosocial well-being of working mothers of preschool children. It investigated the mediation effects of sociological ambivalence in the relations of psychosocial well-being with a family-supportive work environment and with the gender-role stereotype of family members. In addition, it tested the moderated mediation effects of the traditional gender-role attitudes in workplace and meta-mood. Data were obtained from 476 working mothers of preschool children. Using SPSS 25.0, Cronbach's alpha reliability was calculated, descriptive statistics were generated, and Pearson’s correlation analysis performed. Mediation and moderated mediation analyses were carried out using the SPSS process macro 3.5 program. The main results were as follows: first, sociological ambivalence mediated the relationship between psychosocial well-being and a family-supportive work environment. The mediating effect of sociological ambivalence was moderated by emotional attention, a sub-factor of meta-mood. Second, sociological ambivalence mediated the relationship between psychosocial well-being and the genderrole stereotype of family members. In addition, the traditional gender-role attitudes in workplace moderated the mediating effect of sociological ambivalence on the relationship between the gender-role stereotype of family members and psychosocial well-being. These results can be used to inform discussion on changing policy and education to improve the psychosocial well-being of working mothers with preschool children.