Abstract: Accelerating the construction of digital twin river basins is one of the ten priorities of the 2022 National Conference on Water Resources. The Pearl River Resources Commission carried out the pilot work of digital twin Pearl River in key reaches of the main stream of Xijiang river, and explored the realization path of four functions of FEDE (forecasting, early-warning, drill and emergency plan) of digital twin Pearl River flood management: construct the level 2 data baseboard of Xijiang River basin to realize the digital mapping of physical elements of the river basin; establish the model evaluation services to enable intelligent simulation and accurate decision-making of flood management dispatching in the river basin; construct the flood management knowledge maps of Xijiang River by using the flood knowledge database and regulation rule database of Xijiang River basin; ; explore the construction of a digital twin Pearl River allfactor multi-scale flood drill digital scene, and improve the flood management and works scheduling level of the river basin to ensure the flood safety of the Guangdong-Hong Kong-Macao Greater Bay Area.