Research and applying for new scientific and technical advances and modern new models to improve the quality of hydro-meteorological forecasting. This study has built a complete set of integrated tools with modules that update with real-time measured rain data, water level, discharge, and reservoir regulation activities that are integrated into the operating systems. hydrological model (MIKE SHE) for forecasting flow to the lake, regulating reservoirs, hydraulic model MIKE 11 to predict floods in rivers, MIKE 11 GIS model for flood warning for downstream areas. The toolkit uses medium-term (5-day) forecast rain data from the IFS model, which has been calibrated and evaluated as appropriate. The results of the evaluation and trial application of one flood season for the two basins Thach Han and Vu Gia–Thu Bon gave relatively positive results and continued testing for the Tra Khuc–Song Ve basin. This study has built a set of flood warning maps according to water level and flood warning level, which is an important reference document that provides good support for flood forecasting and inundation warning to serve the prevention of natural disasters.