The eco-environment vulnerability assessment was conducted in Huanjiang, a karst region of northwest Guangxi, based on the landscape structure. Grey relational grade analysis was adopted to study the assessment index system, and we finally selected fragmentation, perimeter-area fractal dimension, aggregation index, area proportion of karst landforms, soil erosion index and vegetation coverage index as the evaluation factors to construct the eco-environment vulnerability model to evaluate the vulnerability of landscape types and the regional eco-environment vulnerability degree, semi-variogram analysis and ordinary Kriging interpolation were conducted to get the distribution map of regional eco-environment vulnerability. The results showed that: (1)The vulnerability of the landscapes of forest lands was the highest, followed by unused land and farmland; (2)The semi-variogram analysis showed that the regional eco-environment vulnerability had a relatively good spatial autocorrelation in the study area, and the range of autocorrelation extended to about 25km. The spatial variability of the regional eco-environment vulnerability was in an obvious isotropy within 15km, but existed distinct anisotropy character outside 15km; (3)From the global aspect, the regional vulnerability index was higher in southwest area than that in northeast area, and it was highly related to the elevation. This showed that geology and topography of the study area were the dominant factors affecting the spatial pattern of the regional eco-environment vulnerability．Key Words: karst; landscape spatial structure; eco-environment vulnerability; spatial variation; Guangxi