BACKGROUND: Parenting today is characterized by numerous challenges and stressors. As a well-researched contextual factor for parenting, social support may help parents reduce parenting stress and adopt more positive parenting practices. However, the direct and indirect pathways linking social support to parenting outcomes remain largely unexplored. This study aimed to investigate whether and how the association between social support and parent-child relationships was mediated by the presence of meaning in parenthood and parental self-efficacy. METHODS: As part of a parent education project, a total of 1,242 Chinese parents (87.2% female) participated in questionnaire surveys conducted by this cross-sectional study in Hong Kong. Data were analyzed using SPSS Statistics 26.0 and PROCESS Macro v4.1 for correlation analysis and serial mediation analysis. RESULTS: The results indicated that the presence of meaning in parenthood and parental self-efficacy mediated the association between social support and parent-child relationships, both individually and serially. Furthermore, the mediating effect of the presence of meaning in parenthood was significantly greater than that of parental self-efficacy, as well as the serial mediating effect of the presence of meaning in parenthood and parental self-efficacy. CONCLUSIONS: Social support is positively associated with parent-child relationships, both directly and indirectly, via the presence of meaning in parenthood and parental self-efficacy. Future research could employ the serial mediation model to explore the effects of social support on the well-being of parents and children. Additionally, future practice may prioritize the presence of meaning in parenthood as a crucial outcome indicator for parenting interventions.