Abstract: Effects of underground excavation on the adjacent piles are that the movement of lateral soil on the piles leads to additional pile displacement and bending moment. It may do serious harm to the normal use of adjacent piles when the movement of the lateral soil is large. The 3D finite element software ABAQUS is adopted to study the behavior of passive piles subjected to the movement of the lateral soil by regarding the movement of the lateral soil as the boundary conditions to simplify the process of excavation, and the effects of different modes of lateral movement of soil on pile deflection and bending moment are analyzed. The results from the numerical analysis show that the pile deflection and bending moment are obviously affected by different modes of the lateral movement of soil, such as different maximum displacements, distribution ranges, distribution shapes and so on, which cannot be ignored in practical pile design.