Abstract: Based on the seismo-geological conditions and the potential seismic risk analysis, the authors assess the potential earthquake deformation in Mogao Grottoes area using a 3-D finite element model with a parabola model for horizontal seismic displacement distribution. The seismic displacement and strain are simulated for three seismic magnitudes (Ms): 5.5, 6.0 and 6.5 under the fault activity manner of thrusting and horizontal sliding, which provides guidelines for the design of earthquake resistance and grottoes protection.