Non-point source pollution poses a serious threat to river. therefore non-point pollution model was developed. This non-point pollution model requires detailed spatial data for accurate predictions Geo-spatial Information System(GSIS) is well suited to those needs. The parameters for these models provided by the GSIS were slope, slope shape, field slope length and SCS run off curve number. Hence, this study presents an application of GSIS processing tools for AGNPS model developed by the ARS(Agricultural Research Service) in cooperation with the MPCA(Minnesota Pollution Control Agency) and has developed interface that construct the input data of ASCII type in the AGNPS model using GSIS.