Abstract: Taihu Lake area of Jiangsu Province is located in the Yangtze River Delta, with a dense river network, high urbanization rate, numerous water projects and complex regulation, obvious characteristics of river basins, regions and polder areas, and prominent problems such as regional flood, urban flood and drainage, and polder area drainage. Due to the inherent complexity of the hydrodynamic simulation model of plain river network, the hydrological-hydrodynamic joint simulation of large plain river network is usually difficult to meet the requirements of dynamic update of model data and multi-scale hierarchical simulation. This paper uses the idea of multi-scale intelligent model construction to carry out the construction and simulation of multi-scale intelligent hierarchical model for flooding in Taihu Lake area, and the results show that the multi-scale model can provide rapid simulation and accurate decision-making for flood simulation analysis in Taihu Lake area of Jiangsu Province, and strongly support flood scheduling in Taihu Lake area of Jiangsu Province.