Based on the engineering data of an underground substation in Shanghai, the influence of excavation on the deformation of supporting structure was analyzed according to the measured data. The results show that the displacement of the continuous wall is parabolic during the excavation of the foundation pit, and the displacement value increased with the increase of excavation depth; however, the maximum horizontal displacement position remained near the excavation surface. The deformation of foundation pit structure was affected obviously by the corner effect. The finite element software Plaxis was used to simulate the construction process of the project, and the influence of different construction schemes on the deformation of the foundation pit was analyzed and compared. By validating the numerical simulation results with the measured data, the feasibility and advantages of the reverse construction method were demonstrated.