Abstract: The objective of this study is to simulate the hydrologic responses to a single-storm event with a distributed hydrologic model system(HMS)in the Emei Watershed and to provide information for the study on the interactions between regional climate and hydrologic system in the upper Yangtze River. HMS was designed to study hydrologic processes and systems responding to various climatic factors. HMS utilizes spatial information on climate,soil type,land use and land cover,digital elevation,and hydrologic parameters and simulated variables have physical meaning. In this study,the SCS Curve Number and Green-Ampt methods of rainfall-runoff partitioning were used in HMS. The data sets such as DEM,soil,land use and land cover and hydrologic parameters were processed on GIS. The simulations with different time intervals in precipitation and different methods for obtaining hydraulic conductivity were conducted to examine the effects of temporal scale in precipitation and spatial variation in hydraulic conductivity on the hydrologic responses. The application of HMS was demonstrated for the hydrologic simulation in the Emei stream watershed. It was shown that simulated streamflow compares well with the observed data.