Abstract: The development of county-level Prosperity industries has increasingly exposed inherent sustainability challenges. Existing research predominantly focuses on localized experiences and evaluations, lacking systematic theoretical analysis and empirical contributions from underdeveloped regions. This study constructs a three-dimensional system synergy theoretical framework based on field investigations in Aba Tibetan and Qiang Autonomous Prefecture (Sichuan Province) and Linxia Hui Autonomous Prefecture (Gansu Province), analyzing the value connotation, intrinsic mechanisms, practical dilemmas, and root causes of sustainable development in county-level Prosperity industries. The study found that the County-Level Prosperity Industries in Ethnic Regions have achieved remarkable results in the practice of rural revitalization, and many good practices have emerged, but they still face sustainability risks, including fragile industrial chains, insufficient market efficiency, human capital discontinuity, inadequate social participation, and ecological threshold constraints. To address these challenges, the study proposes:1)A "four-wheel drive" strategy featuring diversified development, innovation- driven approaches, brand building, and financial empowerment to promote high-quality development of county-level wealth-enhancing industries in post-poverty-alleviation regions; 2)A "four-dimensional approach" integrating talent cultivation, incentive mechanisms, career development channels, and public service optimization to consolidate the talent foundation; 3) A "triple strategy" combining green leadership, smart technology empowerment, and ecological compensation to facilitate sustainable industrial development.

Key words: county-level prosperity industries, ethnic regions, common prosperity, sustainable development