The stress state of the sliding soil behind a rigid wall rotating about base is analyzed in detail. The relations among the reactions on wall and sliding surface

and shear stress and vertical pressure of the horizontal soil strata are established. The friction angles of the wall and sliding surface are reduced in order to consider that the soil near base don’t reach the limiting equilibrium state. Based on the horizontal soil slice element method

the stratum by stratum calculational method is set up to obtain the vertical earth pressure acting on the surface of stratum by considering the shear stress of the strata

the change of angle of horizontal of the failure line and the friction angle of the wall. The unit earth pressure

the resultant earth pressure and the point of application of the resultant earth pressure on the retaining wall are also obtained. It is demonstrated that the obtained unit earth pressure is consistent with the experimental observations; and the resultant earth pressure is larger than that of coulomb’s solution. The width of the topper curved sliding surface is smaller than that of coulomb’s solution; but it is consistent well with the engineering observations.