On the basis of Conservation of Resources theory, we investigated how social support from supervisor, co-workers, life partner, and family members is associated with work-family conflicts in N=107 working mothers. We used data from a cross-sectional questionnaire and a standardized diary to examine two possible forms of interplay: (a) Social support as an antecedent of work-family conflicts, and (b) moderating effects of social support on the relationship between domain-specific strain and work-family conflicts. Overall, results favored social support as an antecedent of work-family conflicts. (Contains 3 figures and 6 tables.)