Long distance water diversion projects in the cold regions of northwestern China are influenced by drift ice in winter, the diversion tunnel linings are damaged by various impact force produced by the drift ice with different velocity and impact angles. In order to study the impact of drift ice on the tunnels in these areas, we adopted theoretical analysis in combination with numerical simulations. The results show that when the velocity of the drift ice is fixed, its influence on the tunnel linings increases with the impact angle and the relationship between them shows an approximate nonlinear variation. When the impact angle is fixed, its influence on the tunnel linings also increases with the velocity, but the relationship shows a linear variation. It is also found that the influence of the velocity is stronger than that of the impact angle under various combined working conditions, and the influence of the impact angle on the impact force and tunnel displacement is not evident.