Abstract: Based on the excavation project of a metro transfer station, the change laws of horizontal deformation of the retaining structure with the excavation depth and time are studied. Three-dimensional finite element model is established to simulate the excavation of the metro station. The FEM results and in-situ monitoring results of retaining structure deformation are compared. The results show that the difference of the maximum horizontal displacement of diaphragm wall between the calculated and in-situ monitoring results is small. And the trend of change laws is almost uniform. The results of finite element analysis are credible. Three-dimensional finite element model can consider the influence of spatial effect to the horizontal displacement of diaphragm wall. It may provide reference for the design and construction.