Abstract: An experimental study on gravity dam-reservoir hydrostatic pressure simulation using shaking table model tests was conducted, focusing on the problem in dynamic failure tests ? selecting only water as model reservoir material leads to a model dam body of density inevitably equal to that of the prototype dam. For this end, an added mass was used for simulation of hydrodynamic pressure and a spring system for hydrostatic pressure, so that materials of high density, if needed for improving the model tests, can be selected for model dam bodies. A comparative study on a series of model dams shows that this method, convenient for adjusting model materials, can effectively simulate the hydrostatic and hydrodynamic pressures produced by reservoir water, satisfying similarity requirements. And we found out that in simulation of seismic responses, hydrostatic pressure has an obvious effect on the dynamic characteristic parameters and failure behaviors of a dam structure.