Based on the overlapped conditions on complex river network and basin, a 1D and 2D flood routing model which is based on water-resistance structure of railways, roads, embankment and mobile boundary to realize timely flood regulation in basins of the detention basin was proposed. The model was calculated by using the finite volume method (FVM). A corresponding simulation system of the 1D and 2D flood routing model was set up in consideration of the total frame of flood optimization regulation. Any position's water level, flow speed, water height and submerged time can be acquired from it. The system was used in Dongdian Basin, and reasonable agreement was found between the measured data and the calculated data of Daqing River. The system was also used to simulate the program of five basins combined-regulation in Daqing River Basin, and to analyze the return basin phenomenon, comparing different cases .