Most of the concrete arch DAMS in China are built in the western region, which is rich in water resources and prone to strong earthquakes. The geological conditions in the western region are very complicated, and the dam body is easy to be damaged by strong earthquakes. In this paper, a seismic wave program based on viscoelastic artificial boundary is compiled, and the input ground motion time history is converted into equal effects on boundary nodes. Numerical analysis is carried out on the arch dam, and the dynamic response of the arch dam under several groups of strong earthquakes is explored, considering the effects of ground motion characteristics and dam structure characteristics. Based on the statistical analysis of the river-side displacement, transverse joint opening and damage expansion of the arch dam under the action of the above factors, the variation law of the ground motion peak value of different indexes is found, and the influence mechanism of ground motion intensity on the dynamic response and damage of the dam body is revealed. It can provide design basis for similar projects.