Suction foundation is widely used in the installation and fixation of large offshore engineering structures. In this paper, the finite element analysis software ABAQUS is used to establish a three-dimensional large deformation finite element analysis model based on the coupled Euler Lagrange method (CEL). The finite element numerical simulation of the soil plug uplift process during the installation and settlement of suction foundation is carried out. The finite element simulation results and theoretical calculation are comprehensively analyzed, and the mechanism of soil plug uplift and its weakening the ultimate bearing capacity of suction foundation is obtained.