Abstract: In the drought and cold region of Northwest China, the sluice piers built on the river channel in the long-distance water conveyance project have been damaged by the collision of ice loads. In order to guarantee the safe and stable water supply in winter, it is necessary to study the mechanical characteristics of the collision damage caused by ice loads on the sluice pier. The Arbitrary Langrangian-Euler (ALE) Fluid-Structure Interaction (FSI) method is adopted to simulate the collision processes of an ice wedge into the sluice pier under different collision conditions. By comparing experiment results, the applicability of the ice material model parameters and the ALE algorithm is verified, and the influence of mesh sizes on collision force is analyzed. The research results show that the extreme values of the collision force on the sluice pier obtained from the calculation are in good agreement with the experimental values, and the parameters of the ice material model, the ALE algorithm as well as the mesh sizes adopted in the simulation of this paper can simulate the applied ice load force on the sluice pier accurately. The damage and deformation of the sluice pier as well as the damage of the ice sheet are mainly concentrated in the collision contact zone, and the scale of collision force in the contact zone is influenced by the 'Water Cushion Effect', while the air medium has less influence on the collision force. The time-history curve of the collision force under the working conditions of different ice thicknesses and ice speeds presents a 'Sawtooth' phenomenon, as the loading-unloading time of the collision force is relatively shorter. In the process of wedging the ice sheet into the sluice pier, the extreme value of the collision force appears in the 0° positive contact zone, as the collision force decreases gradually in the range of ice velocity 1.2 m/s~3.0 m/s. Without changing the ice speed conditions, the response of pier structure increases with the increase of ice thickness, and the top displacement of the sluice pier under both working conditions of ice speed and ice thickness shows the periodic vibration. The simulation results are intended to provide guidance on the structural safety of the sluice pier on the river channel in the drought and cold region of Northwest China during the ice period.