Soil nitrogen is necessary nutrient elements for plant in agricultural ecosystem，and excessive nitrogenous fertilizer is one of the main reasons of rural surface source pollution and water eutrophication. Therefore, understanding the spatial variability of soil nitrogen is vital for agricultural production and ecological environment protection. Qionghai lake is the second largest inland plateau freshwater lake of Sichuan Province. And it is important conservation areas for drinking water and nature reserve. Presently the water quality of Qionghai lake was mesotrophic status. Excessive nitrogen from rural surface source pollution was one of the main pollution factors. In this research, 386 soil sample points were selected by using random sampling method in Qionghai Basin，and soil physical and chemical properties were analyzed. Furthermore，spatial variability of soil nitrogen in the surface layer of this region was analyzed by using the geostatistics and GIS method，and its influential factors were also analyzed by means of variance analysis and buffer analysis．The results showed that the contents of soil total nitrogen (TN) and available nitrogen (AN) were (1.85±0.51) g/kg and (138.5±47.7) mg/kg, respectively. Variable coefficients of TN and AN were 27.52% and 32.24%, respectively, which belonged to a moderate level. Geostatistical analysis suggested that the spatial autocorrelations of soil TN and AN were moderate level，and random factors played a more important role in spatial variability than structural factors．The spatial variability of soil TN and AN were anisotropic, and obvious in northeast—southwest direction. TN and AN in the area were distributed in band and patches．Regions with high soil TN and AN contents were mainly distributed in southeast suburbs of Xichang City, and decreased gradually to north, east and south. Regions with low soil TN and AN contents were mainly distributed in north lakeshore zone of Qionghai lake. Spatial variability of soil TN and AN was significantly influenced by land use types, soil parent materials, soil textures, soil pH values as well as distributions of citiy, town, river and Qionghai lake. There was no significant correlation between spatial variability of soil TN and AN contents and roads.