The stream network analysis is used to quantify the geomorphological properties of the mountainous basin and examine the relationship between sediment delivery and geomorphological parameters in catchments. It was examined to analyze the stream network by using 50m-DEM data on GIS at a study area of Yudagiri River. The results are as follows. The channel network made from 12m-DEM which was resampled by 50m-DEM on GIS was the closest to that by manual operation. The relative error of stream order analysis indicated the value of 25.5% at the maximum. Moreover, the maximum relative error of DEM(C-DEM) made from the contour line in 1/25, 000 maps is 11.5% smaller than that of the resampled 50m-DEM.
