This study investigates the association between work-family conflict and organizational citizenship behavior and examines the mediated role of subjective happiness between and the moderated part of family support. A moderated mediation model is established based on the Conservation of Resources theory. We collected data from 386 employees of nine companies in China. This study shows that the work-family conflict of female professional employees is negatively correlated with organizational citizenship behavior, and that the relationship is mediated by subjective well-being. Furthermore, female (...) professional employees’ family support moderates the effects of work-family conflict on subjective happiness and organizational citizenship behavior, with the relationship weaker when family support is higher. This study enriches the literature on work-family conflict by using family support as a mediating mechanism for work-family conflict. It enhanced our understanding of the influencing mechanisms of organizational citizenship behavior by constructing a more detailed model. (shrink)