Aims: To explore how family functioning and family resilience mediate the relationship between disability severity and quality of home-based care among families with disabled older adults. Methods: A cross-sectional survey was conducted with 431 families with Uygur and Kazakh disabled older adults in Xinjiang, China, in 2020. The data were collected using the Katz Activity of Daily Living Scale; Mini-Mental State Examination; Family Adaptation, Partnership, Growth, Affection and Resolve Index Scale; Family Resilience Assessment Scale; and Family Caregiving Consequences Inventory Scale. All mediation effects were estimated in SPSS26.0. Results: Disability severity, family functioning and family resilience were all significantly correlated with home-based care quality. Disability severity had a 46.16% direct effect on home-based care quality and a 53.84% indirect effect on home-based care quality independently and in series through family functioning and family resilience. Conclusions: Disability severity directly affected home-based care quality and had an indirect influence via family functioning and family resilience. Multidisciplinary care teams should focus on families with disabled older adults and help them improve family functioning and family resilience by implementing targeted interventions, so as to improve home-based care quality.