Abstract: The digital elevation drainage network model(DEDNM)was established based on the digital elevation model(DEM)considering the spatial watershed heterogeneity.The watershed was divided into a series of discrete sub-cells as the runoff generation and confluence calculation units,and the area weighting of each sub-cell was calculated.The digital hydrological model(DHM)was constituted by coupling the DEDNM with Xin’anjiang model,a lumped hydrological model.The integrated flood forecast system was based on a client/server(C/S)mode.The flood forecast system was applied in two reservoirs,Meishan Reservoir and Nianyushan Reservoir which belong to the Shiguan River watershed — the intensified observation field of GEWEX Asian Monsoon Experiment(GAME)project.The results show that the established forecast system not only performs well in simulating flood process of reservoir inflow,but also satisfies the precision requirements of the real-time flood forecast.It provides approaches to make full use of available spatial technologies and data for rainfall-runoff modeling and technical improvement of hydrological forecast.