Abstract: As the background of Hangzhou Metro Line 4 shield passing through a power tunnel, the influence of the shield directly cutting pile foundation on surface settlement is studied through three-dimensional numerical simulation. The thrust force of palm face and synchronous grouting pressure are used as tunneling parameters for numerical simulation, and field monitoring data is obtained and analyzed. The simulation data confirm that: the surface settlement is large and the settlement rate is fast during the pile cutting period, and both the settlement amount and the settlement rate decrease with the increase of the distance between the monitoring point and the tunnel axis. Due to the particularity of the structure of the power tunnel, the settlement generated in pile cutting process accounts for a small proportion of the total settlement. The thrust force of the palm face has a great influence on the heaves of the surface before pile cutting and less on the surface settlement amount during pile cutting. The grouting pressure has little effect on the heaves of the surface before pile cutting and the surface settlement amount during pile cutting. By comparing the field data with the simulated data, it is found that the surface settlement caused by pile cutting has a certain lag in the field data. According to the numerical simulation results, it is suggested that when the distance between shield machine and pile foundation is greater than 6 m in the construction process, the thrust of the palm face should be appropriately increased to reduce the final settlement of the surface. When the distance is less than 6 m, the thrust should be adjusted back to 100% static earth pressure to reduce the horizontal displacement of the pile and to ensure the smooth operation of pile cutting.