The authors list the main influencing factors causing the failure of the country rock of the Longmen Grottoes in Luoyang City, Henan Province. Using finite element method, the authors study the dynamic displacement, velocity, and stress variation of the country rock under different seismic loads and determine the locations where the maximum displacement, maximum velocity and stress concentration appear. Then, the authors compare the displacement, velocity, and stress of the country rock which has fractures with the ones of the ROCR which has no fractures. On the basis of the Mohr-Coulomb Failure Criterion, the authors study the possibility of failure of the country rock.