Abstract:Terrain factors have a profound impact on land quality and land use in urban land grading.Based on land grading technique and the combination of Tonghua county land classification,this paper applied GIS system to generate regional DEM,took the establishment of ground slope and ground aspect date model for example and put forward a new method about how to quantify terrain factors in urban land grading.According to topographic constraints of urban planning,this paper usd space analysis module to quickly strike the factor scores and total score of mass of grid unit and scientically quantify the terrain with the final objective to reflect the law of real spatial distribution of urban land quality differences.