Abstract: To comprehensively assess the spatiotemporal evolution characteristics of ecological environment quality in the Huaihe River Eco⁃Economic Belt， the remote sensing ecological index （RSEI） data， combined with multi⁃source data including topography， climate， vegetation coverage， land use type， GDP， population density， and nighttime light were utilized. The methods such as univariate linear regression analysis and the center of gravity migration model were employed to reveal the spatiotemporal variation characteristics of ecological environment quality in the Huaihe River Eco⁃Economic Belt from 2001 to 2021. Furthermore， the geodetector was applied to deeply analyze the quantitative impacts of key factors and their interactions on ecological environment quality. The results indicated that： 1） The interannual variation of ecological environment quality in this region had exhibited fluctuations， with an overall trend of stable improvement. Spatially， the ecological environment quality had shown a pattern of being higher in the southwest and lower in the northeast， with significant differences in the area proportions of different quality grades. 2） The spatial agglomeration dynamics of regions with different ecological environment quality grades had been complex and diverse， generally migrating toward the northwest. 3） Among natural factors， the slope and elevation have had the greatest impact on ecological environment quality， while among socioeconomic factors， the influence of land use type and nighttime light had gradually strengthened. The interaction between topographic factors and relative humidity， precipitation， and other factors had exerted a significant influence on the spatial distribution of ecological environment quality. The research findings might provide a scientific basis and decision-making support for ecological environment protection strategies and sustainable development pathways in the Huaihe River Eco-Economic Belt.