Abstract: The modern meteorological service technology development, especially quantitative precipitation estimation and forecast technology, makes it possible to improve the hydrological meteorological forecast service. Based on real-time hydrological and meteorological monitoring, quantitative precipitation estimation (QPE), quantitative precipitation forecasting (QPF), real-time flood forecast technique, hydrometeorology forecast system of the Danjiangkou Basins in Hanjiang applies high spatial and temporal resolution rainfall data in hydrological model to carry out the real-time hydrometeorology forecast. Adopting the browser/client/server (B/C/S) three-layer structure, the rainfall monitoring, radar quantitative precipitation estimation, numerical forecast precipitation, flood forecast, hydrology and other product information are processed on client/server (C/S) system, and then the products can be displayed on the browser side. GIS technology is used to define the basin boundary and extract the river system based on the DEM data, and then to define the place and water in basin, to complete the digital work of basin basic information. Second, precipitation information, basin actual observation, radar estimation, model forecast precipitation products are processed with some clipping algorithm and basin geography information, and input into the hydrological model. Third, to construct basin hydrological forecast model based on basin geography climate characteristics, the Xinanjiang Hydrological Model is adopted to make the real time flood forecast, and the data files are stored in specified directory for database calling. Finally, the Asp.Net (C#) 4.0 is adopted to develop system display platform, including the display for basin overview, graphics products of basin actual monitoring, radar QPE, model QPF, hydrological forecast and monitor products. The completed system platform can achieve the hydrological meteorological information monitoring and forecasting. During the two flood processes in July of 2010 and September of 2011, the precipitation observed and forecasted is given and displayed timely and accurately, the flood process curve is also forecasted accurately. Nowadays, the system has been successfully transplanted to the Three Gorges, Qingjiang Shuibuya Reservoir, Huaihe Wangjiaba, the Zhanghe Basins, and has carried out flood tests and services, achieving good effects.