Abstract: As a critical wetland ecosystem in the Yangtze River Basin, the Dongting Lake region has undergone substantial ecological reorganization under land use transitions. This study quantified the spatiotemporal coupling relationships between ecosystem service value (ESV) and landscape ecological risk (LER) in response to land use/cover change (LUCC) during 1996-2020 through multi-temporal remote sensing analysis. The results revealed that the cropland consistently expanded, while grassland and unused land decreased. Water bodies experienced a fluctuating decline, whereas forested areas and built-up land increased.ESV initially declined before rebounding, ultimately resulting in a net reduction of 21.247 billion RMB (8.33%), while LER showed a slight but consistent downward trend, with an average decline from 0.7814 to 0.7332. Water bodies were identified as both high-value ESV providers and high-risk LER areas, with stable ESV hotspots in lake water bodies and cold spots primarily in surrounding forested and grassland areas. Meanwhile, LER hotspots showed a shrinking trend within water bodies, with an increasing spatial aggregation, whereas cold spots remained in forested and grassland areas. The coupling coordination degree between ESV and LER followed a “decline–increase” pattern, with water bodies exhibiting a higher coupling degree than other land use types, indicating a state of “moderately coordinated development.” Spatially, the coordination degree was higher in central areas and lower in peripheral regions, reflecting “relatively imbalanced” and “barely balanced” development outside water bodies, while areas with high coupling coordination showed an expanding trend. These results elucidated complex LUCC-ESV-LER interdependencies in watershed ecosystems, and provided critical insights for optimizing ecological security frameworks and enhancing value realization mechanisms in major river basins.