Abstract：The dynamic stability of a slope in Xiaowan hydropower station is studied under the blasting load with the dynamic FEM. By means of a special dynamic interface contact element，the coupling behavior of the blast wave propagation property and the dynamic response of the contact element are also considered in the analysis. Numerical results indicates：(1) the stability of the whole slope can be ensured even under the largest blast loading conditions；(2) the local instability could happen at the vicinity of the blast holes because the particle velocities in this area are much larger than the allowable velocity；(3) interface elements on the sliding surface of the slope are most opened by the blast waves，which might be a dominant factor controlling the whole stability of the slope.
