Abstract: Based on ANSYS super-element analysis technology, the whole pool super-element model of spent fuel storage grid is established to simulate the grid response more accurately. Considering the effect of fluid-structure coupling between the grids, the nonlinear time-history seismic analysis of the whole pool grids is carried out, and the calculation results of jump displacement, collision acceleration and slip displacement of the grids are obtained. The super-element model seismic analysis results are extended to the detailed grids model to obtain the deformation and stress of the grids under earthquake. The method based on super-element analysis and model building can significantly improve the efficiency of calculation, and the calculation of grid response is more accurate. It can be used in the seismic design of spent fuel storage grid.