Care for U.S. children living with serious illness and their families at home is a complex and patchwork system. Improving home-based care for children and families requires a comprehensive, multilevel approach that accounts for and examines relationships across home environments, communities, and social contexts in which children and families live and receive care. We propose a multilevel conceptual framework, guided by Bronfenbrenner's ecological model, that conceptualizes the complex system of home-based care into five levels. Levels 1 and 2 contain patient and family characteristics. Level 3 contains factors that influence family health, well-being, and experience with care in the home. Level 4 includes the community, including community groups, schools, and providers. Level 5 includes the broader regional system of care that impacts the care of children and families across communities. Finally, care coordination and care disparities transcend levels, impacting care at each level. A multilevel ecological framework of home-based care for children with serious illness and families can be used in future multilevel research to describe and test hypotheses about aspects of this system of care, as well as to inform interventions across levels to improve patient and family outcomes.