In order to verify the rationality of the simplified calculation method for the stability of rigid retaining wall with finite soil body under the state of slope release. In this study, various influencing factors such as soil cohesion, friction between the fill and the back and bottom of the retaining wall, as well as the load effect on the top surface of the fill were considered, and a theoretical model of the retaining wall stability was established. Based on the upper limit method of limit analysis , the stability coefficients of the rigid retaining wall with a finite soil body under the state of slope release were obtained. The results show that the stability coefficient of the retaining wall Fs is proportional to the soil cohesion c, the wall-soil interface friction angle δ, the bottom friction angle δa, the wall-soil interface cohesion cw, the bottom cohesion cl, and the internal friction angle of the soil [φ]. It decreases with the increase of the width-to-height ratio l/H, and gradually tends to be stable. In addition, the rationality of this simplified calculation method is verified by comparative analysis with the Cullen method.