The traditional rigid-body limit equilibrium method and finite-element-based strength reduction method has some problems in stability and reinforcement analysis. Based on deformation reinforcement theory (DRT)

a stability analysis method of slope is presented with elastoplastic finite element analysis. Plasticity complementary energy(PCE) is used to evaluate the whole stability of slope; and safety factor of slope can be obtained through the PCE curve with strength reduction factor. Reinforcement location and force can be determined by unbalance force distribution in the slope. Possible sliding surface also can be located on the boundary that direction reverse of unbalance force occurs. Three classical examples of slopes has been modeled and analyzed. The safety factor and reinforcement key location and force have been determined by the PCE curve and unbalance force distribution. The results indicate that the DRT based on nonlinear finite element analysis is effective in analysis of stability and reinforcement for rock and soil slopes. The failure process can be reflected by the development of unbalanced force with the strength reduction.