In this paper, the spatial neighboring length and number between oasis types and desert or salina-marsh in the Jinta Oasis located in the arid Heihe River Basin of Northwest China were calculated by using ArcView3.0a and buffer zone analysis methods, and the threatening degree of oasis ecological security was discussed. The results indicated that it was different in neighboring length and number between oasis types and desert or salina-marsh, and the influencing area by desert and salina-marsh patches was also different. Grassland and farmland had more neighboring length and numbers with desert or salina-marsh patches, and impacted by desertification seriously. Forest and farmland had more length and numbers adjacent to salina-marsh, and influenced by salinization severely. The assessment of ecological security based on spatial analysis could reveal the threatening degree of oasis by desertification and salinization.