Soil and Water Assessment Tool(SWAT) model is an advanced distributed hydrological model which is based on physics mechanism and integrated with Remote Sensing(RS),Geographic Information System(GIS) and Digital Elevation Model(DEM) techniques.In order to study temporal and spatial tendency of hydrological processes and find out a relationship among hydrological temporal and spatial process,meteorology and physiographic characteristics of river basin,yearly and monthly runoff simulations(1981-1985) were applied to Madao catchment located in the upper reaches of the Han River.After ascertaining the optimal parameters,satisfied simulation results were obtained with the accuracy of 0.9427 for Nash-Sutcliffe coefficient over the 5 year continuous monthly simulations on discharges,which suggest an excellent modeling performance of SWAT2000 in the study area.6 referenced sub-drainage basins were selected in the upper reaches of the Madao main river way,and topographic parameters were obtained using software of River Tools in each sub-drainage.Monthly runoff simulations were then applied to them with the same parameters as Madao catchment,the responses of runoff simulation to topographic parameters were studied,and the Normalization of Runoff-total Length Index(NRLI) were presented.Analyses indicate that NRLI is influenced by source density.NRLI fluctuates tempestuously as source density decreases sharply.Nevertheless,it still trends towards the constant 1 in Madao catchment.