Abstract: In underground structure, excavation method has a great impact on land subsidence and structure stability. In order to choose a more appropriate excavation method, the finite difference procedure FLAC is adopted to simulate the two different excavation process design schemes of a subway station somewhere. The dynamic change of stress in soil and forces in support structure is analyzed. It is found that after the excavation of the adit, a large depressed zone will form in both the roof and the floor. The displacement induced by the adit accounts for almost 60% of the total displacement. The maximum axial force and moment in the support structure occur in the middle of floor or at the conjunction of arch and sidewall. The displacement of the two excavation methods is quite similar. These conclusions provide important reference for the design and construction for the station.