ObjectiveThis study explored the related factors of FQOL in parents of children with ASD and examined whether social support mediates the relationship between parental self-efficacy and FQOL in parents of children with ASD. Design and methodsUsing a cross-sectional design, a total of 260 parents of children with ASD were recruited from September 2019 to November 2020. They completed the Beach Center Family Quality of Life Scale, the Parenting Sense of Competence Scale, and the Social Support Rating Scale. ResultsParental self-efficacy and social support explained approximately 49.5% of the variance in FQOL. After controlling for the confounding influence of parents' education level, parental self-efficacy had a direct effect on FQOL (β = 0.292, SE = 0.108, P < 0.01) and an indirect effect on FQOL (β = 0.165, SE = 0.069, P < 0.01). Effects were mediated through social support, with partial mediating effects accounting for 36.11% of the total effect. ConclusionsBoth parental self-efficacy and social support are critical to promoting FQOL, and a partial mediating effect of social support was established. Practical implicationsInterventions for families with children with ASD should focus on enhancing parental self-efficacy, followed by a perceived social support and FQOL prompt.