Oriented to examine the impacts of scales of topographic parameters in regional soil erosion assessment,filtering method was applied to generalize fine resolution DEM(cellsize = 5 m) in ERDAS and ArcGIS systems.The effects of generalization have been assessed by comparing the general topographic characters,statistical analyzing of derived slopes and curvatures,as well as resultant contours and streams.The results show that fine resolution DEMs can be generalized,and the generalized DEMs,with a scaling factor of 5 or 10,and a 3*3 filtering window,are comparable to 10 m resolution DEMs and 1∶50 000 topographic maps in representing ground reliefs.