Abstract: In the finite element analysis of radial gate, the numerical simulation results are usually different by different modeling methods.Aiming at this problem, the large open-top radial gate of Shatuo Hydropower Station on Wujiang River in Guizhou Province was taken as an example, the influence of two modeling methods(node coupling method and thickness superposition method) for flange panel of main beams on the static and dynamic calculation results(three-dimensional nonlinear statics, modal analysis and transient dynamics) of the gate was explored from the perspective of calculation principle.Through comparative analysis, it was found that the simplified method of thickness superposition increased the stiffness of the component, which was unfavorable to the static review of the gate.The two modeling methods had little effect on the vibration mode and natural frequency of the gate under dry and wet modes.The vertical vibration degree of the arm calculated by the node coupling method is slightly larger than that of thickness superposition method, and the dynamic stress of the sensitive area at the connection between the arm and the main beam calculated by the node coupling method was significantly larger than that by the thickness superposition method.The two modeling methods had limited influence on the overall structural properties of the gate.When calculating and checking sensitive areas such as the connection between the arm and the main beam, the node coupling method should be adopted as far as possible to get more safe results.