The formation and development of desertification always depend on two of factors: wind power and characteristics of the underlying surface Pattern sand types of land use are parts of reflections of the latter,which would certainly influence the formation and its development desertification.With Duolun County located on the Inner Mongolia Plateau in semi arid climate region as a typical representation, this paper deals with how to adjust land use types so as to improve the characteristics of the underlying surface and to control desertification The following steps are adopted for accomplishingthis objective:1) Compiling current situation map of present land use of this countyby using Landsat TM image data 2) Considering thegoal is desertification control and prevention, the following three factors like material composition of the earth surface vegetation cover degree of the earth surface and content of organic matter are used as indexes to assess ecologic safety Four grades of safety, semi safety, semi non safety and non safety are distinguished Each land use unit corresponds to a certain grade of safety, so that a map of the county level ecologic safety assessment is obtained 3)Identifying three principles for adjusting land use types:(a) collocation of macroscopic land use pattern should consist with large scale geomorphologic types or large regional geomorphologic difference, (b) ecological safety under condition of free from redesertification; and (c)actual present land use condition should well be considered 4) Adjusting land use pattern and types respectively in semi non safety and non sefety areas Land use types involved in the adjustment include farmland, grassland, open forest, sandy land, saline alkali land etc accounting for 25 8% of the county's total land area. All of the adjusted land use units are shown on the map at a scale of 1∶250,000 Besides, a primarily study on pattern of land use of this county before and after adjustment is also done