Abstract: In order to study the failure mechanism and reinforcement technique of reinforced earth retaining walls, the reinforcement project of a crossroad was taken as an example. The failure mechanism was analyzed firstly. A united measure of shotcrete lining on the surface, pre-stressed anchor and injection was applied. Main problems in construction were discussed and solved. Lastly, the reinforcement effect was simulated with FLAC^2D. After the reinforcement, stable stress and little deformation indicate the united measure is effective.