At present, calculation of the earth pressure of retaining walls mostly adopts the horizontal layered research method. In the calculation and analysis with this method, it is often assumed that the vertical normal stress and horizontal shear stress on the interface of the layered element are uniformly distributed, and influence of the uneven distribution of the interface stress on the earth pressure calculation results is not considered. Based on the existing backfill stress distribution and principal stress deflection law, the shear stress and normal stress that are unevenly distributed on the interface are equivalent to the concentrated force acting on the boundary of the wedge element. Based on the analysis of its static equilibrium conditions, a new method for the active earth pressure analysis of retaining walls that can consider the influence of uneven distribution of shear stress and normal stress at the element interface is established, and the influence of uneven interface stress on the calculation results of earth pressure is discussed. The research results show that the non-uniform interfacial stress of the layered element, as the internal force of the soil inside the sliding wedge, will not affect the magnitude of the resultant earth pressure, but will affect the distribution of the earth pressure and the position of the resultant action point, and it is relative to the resultant earth pressure. Horizontal shear stress and vertical normal stress have greater influence on the calculation results of earth pressure. By comparison and demonstration, it is found that the calculation results can describe the distribution law of earth pressure with reasonable accuracy when considering the uneven distribution of interface stress. The inflection point of the earth pressure distribution curve increases with the decreasing
\delta and increasing
\varphi , and the position of the action point of the resultant earth pressure increases with the increasing
\delta /\varphi .