Based on the results of the seismic response analysis on an embankment dam with asphaltic concrete impervious zone on the upstream face, which was severely damaged by cracking during an earthquake, evaluation method of seismic performance and safety was discussed in terms of the dynamic strain developed in such facing zone. Two methods of safety evaluation were proposed and compared to confirm their applicability in practice; one is to examine seismic safety by comparing the maximum computed value of dynamic strain with the tensile strain at failure obtained in axial tension tests on the facing materials, and the other by utilizing the concept of fatigue, accumulated damage caused by the application of cyclic strain. By taking strain rate dependency of materials into account, both procedures indicated relatively consistent results in damage evaluation.