To study dynamic response of a furnace slag high slope after treatment,the seismic response of the slope was calculated with the finite difference software Flac^3D based on the fully nonlinear dynamic analysis theory,and the acceleration amplification coefficient,dynamic displacement and the plastic yielding zone were obtained.The results showed that the action of dynamic load led to the top of retaining wall of a furnace slag high slope with accelera-tion amplification coefficients at about 1.44 and 3.34 respectively for the vertical direction and horizontal direction and with more safe reserves;the maximum magnitude of the horizontal displacement for the slope is not great and the plastic zones’ area is smaller after treatment,i.e.the stability of the furnace slag high slope is greatly improved and the treatment measures are effective.