This study examined the mediating effects of social support on the association between disaster distress and mental health outcomes. We analyzed the data of 1006 participants with either direct or indirect exposure to one or more disasters. Disaster distress, social support, depression, and anxiety were significantly correlated. Multiple regression and mediation analyses with bootstrapping showed that social support was a partial mediator between disaster distress and depression, and between disaster distress and trait anxiety. It was a complete mediator between disaster distress and state anxiety. The results suggest that enhancing social support may reduce the negative effects of disaster distress on depression and anxiety. Therefore, comprehensive interventions incorporating disaster distress management and enhanced social support are essential in national disaster management policies and psychiatric and mental health nursing services for individuals who have experienced disasters.