Arch dam deformation is comprehensively affected by water pressure,temperature,dam’s structural behavior and material properties as well as other factors.Among them the water pressure and temperature are external factors(source factors) that cause dam deformation,and dam’s structural behavior and material properties are the internal factors of deformation(resistance factors).The dam deformation is the result of the mutual game playing between source factors and resistance factors.Therefore,resistance factors of structure and materials that reflect resistance character of arch dam structure are introduced into the traditional model,where structure factor is embodied by the flexibility coefficient of dam body and the maximum dam height,and material property is embodied by the elastic modulus of dam.On the basis of analyzing the correlation between dam deformation and resistance factors,the game model of safety monitoring for arch dam deformation is put forward. Arch dam deformation is comprehensively affected by water pressure, temperature, dam’s structural behavior and material properties as well as other factors. Among the water pressure and temperature are external factors (source factors) that cause dam deformation, and dam’s structural behavior and material properties are the internal factors of deformation (resistance factors). The dam deformation is the result of the mutual game playing between source factors and resistance factors.Therefore, resistance factors of structure and materials that reflect resistance character of arch dam structures are introduced into the traditional model, where structure factor is embodied by the flexibility coefficient of dam body and the maximum dam height, and material property is embodied by the elastic modulus of dam. On the basis of analyzing the correlation between dam deformation and resistance factors, the game model of safety monitoring for arch dam deformation is put forward.