Abstract: This paper develops a new dynamic particular solution boundary element method to solve the dynamic interactions of damreservoir-foundation system inthetim edomain,studies the influences of elasticity of foundation.fluid of reservoir and damping of system to dynamic characteristic、hydrodynamic pressure and dynamic amplify factor,and calculats the earthquake response of system by using Wilson-θ method. The results show that the method proposed in this paper can treat conveniently the coupling problems of the system,reduces a lot of computing work and has a good precision.