[Objective] A comparative analysis framework covering both border and non-border areas was constructed in order to comprehensively reflect the spatiotemporal patterns and evolution characteristics of coordinated development in Xizang Autonomous Region, to clarify its inherent differences and commonalities, and to provide a scientific basis and policy reference for counties in Xizang to coordinate ecological protection and highquality economic and social development. [Methods] The entropy value method, coupling coordination degree model, obstacle factor diagnosis method, and grey prediction model were employed to empirically analyze the coordinated development level of ecological-economic-social systems across 74 counties in Xizang from 2011 to 2023. [Results] ① From 2011 to 2023, the development levels of ecological, economic, and social subsystems in various regions of Xizang steadily improved. Overall, a spatial pattern was observed characterized by higher development levels in border counties and relatively slower development in non-border areas of the central region.② The temporal evolution of the overall coupling coordination degree showed a sustained positive trend, with border areas significantly higher than non-border areas. Spatially, the distribution showed a pattern of higher levels in the southeast and lower levels in the northwest.③ The main factors constraining the improvement of regional coupling coordination included indicators such as per capita retail sales of consumer goods（C₃）, the share of fixedasset investment in GDP（B₄）, and net primary productivity（NPP, A₂）. Insufficient improvement in ecosystem productivity remained the core constraint on system coordination in border areas, whereas non-border counties faced primary obstacles within their economic and ecological subsystems.④ Grey prediction results showed that from 2024 to 2035, the ecological-economic-social coupling coordination degree of counties in Xizang would steadily increase, and regional coordination would continuously improve. [Conclusion] The ecological-economicsocial systems in counties of Xizang remain in a ‘dysfunctional' stage, characterized by significant regional development disparities. There is considerable room for enhancing the coupling coordination degree among the three systems.