<p>Against the dual backdrop of population aging and China’s Rural Revitalization Strategy, investigating the mechanisms through which the built environment in traditional settlements is associated with older adults’ health is of substantial significance. Taking traditional Dong ethnic settlements in Western Hunan as a case study, a theoretical model encompassing “objective environment-subjective perception-behavioral mediation-health outcomes” was constructed to examine the associations and pathways linking the built environment to older adults’ health, with leisure activities and social participation considered both as independent and sequential mediators. The findings revealed that: (1) objective built environment shows no direct association with older adults’ health; rather, its health-related benefits appear to be entirely mediated by leisure activities and social participation; (2) perceived built environment is not only directly associated with older adults’ health but also demonstrates indirect positive associations through leisure activities, social participation, and their sequential mediation pathways; (3) within the context of traditional “acquaintance societies,” social participation holds a central position, with leisure activities further associated with health through their relationship with social participation, thereby creating a hierarchical mechanism of association. The findings suggest that the health benefits of traditional settlements may not originate from the physical space per se, but appear to be deeply embedded in residents’ subjective environmental perceptions and sociocultural practices. This research expands the contextual scope of built environment and health research and deepens understanding of health-related behavioral mechanisms among older adults in traditional communities. The findings provide theoretical reference and empirical evidence for the development of age-friendly rural environments and the advancement of healthy aging practices.</p>