<p>Ecotourism development, a key strategy for natural and cultural heritage protection and rural revitalization, faces a global challenge in understanding its complex impacts on community well-being. Existing theories have limited contextual adaptability and explanatory power for the structural elements of well-being. This study draws upon social exchange theory, spillover theory, and embeddedness theory to construct an integrative, multidimensional model for the formation of well-being. Based on a case study of residents in the ethnic areas of Western Sichuan Province, China, and an analysis of 402 questionnaire survey results, the following conclusions are drawn: First, contrary to the equal-weight assumption of spillover theory, residents assign greater weight to social governance and social security than to economic development in their assessment of well-being. Second, while perceived economic impacts positively affect well-being, perceived socio-cultural impacts exert a significant inhibitory effect, functioning as a suppressing mechanism that partially offsets the positive contributions of place identity, social capital, and other favorable factors. Finally, structural embeddedness plays a key yet selective moderating role, amplifying the positive effects of endogenous resources such as place image and social capital, while attenuating the impact of external institutional resources such as government trust. The analysis provides an integrated framework for understanding well-being among ethnic destination communities, with key policy implications for sustainable tourism governance.</p>