Abstract: The construction of a new station crossing the existing subway station at zero distance is bound to have negligible impact on the operational safety and structural deformation. In the case study of a metro project in Nanjing City, the open-cut foundation pit is symmetrically excavated by adding a row of isolation piles between the pit and the existing station structure, while the buried excavation construction adopts bench method and the symmetrical construction of left and right guide holes. According to the finite element numerical simulation, the near surface subsidence and the deformation of the existing station structure caused by foundation pit excavation are analyzed, the maximum value of settlement is 9.8 mm, the new maximum settlement of the existing structure is 2.9 mm, and the cumulative settlement is 8.3 mm, thus the safety of the existing structure is ensured.