Abstract: In current water conservancy engineering and flood management, the propagation of flood waves from reservoir discharge is a matter of great concern.Taking the Yichang-Datong section in main channel of Changjiang River as an example, a one-dimensional hydrodynamic model was constructed to simulate the propagation characteristics of flood waves under different working conditions and to compare and analyze the flood evolution patterns along the course.The research results show that: ① The formation of break wave floods can shorten the peak arrival time in downstream sections to varying degrees.With the increase of break wave flow, the distance of river sections where flood waves propagate as kinematic waves significantly shortens, and the flood wave deformation index increases; ② With the extension of the duration of peak flood flow, the distance of flood wave propagation with kinematic wave characteristics will also be shortened, and the flood wave deformation index will increase.However, the peak arrival time at the same site or a certain mileage will be delayed, and the duration of the peak flood will be extended; ③ Under multi-beam break wave conditions, the calculated wave speed is generally higher.As the distance along the course increases, the deformation index declines, but the decay process of the deformation index along the course under multi-beam propagation conditions is significantly slowed down; ④ When there are tributary inflows, the changes in peak flow at sites along the course all exhibit significant inconsistencies, and the duration of high flow is significantly extended.The research findings are of great significance for revealing the propagation laws of flood waves from reservoir discharge and can provide references for regional flood management.