In order to study the dynamic response of the concrete gravity dam during earthquake, the correctness of the ABAQUS 3D added mass subroutine was proved through the simulation of Koyna earthquake, and the dynamic responses of Taolinkou dam under the action of the Qian’an seismic waves were simulated. And studies of the influences of three directions of the earthquake acceleration during earthquake have been carried out. It is found from analysis results that the damage did not occur, but the maximum tensile stress of the downstream mutation reached 2.56 MPa, less than the critical value of the dynamic tensile strength of concrete 2.6 MPa slightly, to which more attention should be paid in the design. In the design, the slope is advised to make a circular arc shape in order to reduce the stress concentration. During the earthquake, the displacement in the vertical flow direction reached 17.87 mm, which is extremely easy to cause the adjacent dam to collide. So during the construction of works, it can be avoided by transverse joint grouting. Counting the earthquake actions of three directions at the same time is the most unfavorable for the dam body, and the acceleration of the vertical direction and the acceleration of vertical rivers direction all have important influences on the seismic analysis. And the practice of only considering the seismic action of a certain direction is seriously distorted. This seismic simulation analysis is expected to provide more insights into the seismic performance of the gravity dam and to optimize the seismic measures.