Considering the influence of principal stress rotation, time effect and wall back inclination, a new solution of seismic active failure angle is derived by using pseudo-dynamic method according to the total force balance of sliding soil. Through the horizontal differential layer method, a new differential equation of the normal seismic active earth pressure and its coefficient of the inclined rigid retaining wall under translation is obtained. Then, the Runge-Kutta method of ordinary differential equation is used to obtain the numerical solution, and the influence of parameters (i. e. vibration cycle time, wall back inclination, internal friction angle of backfill, wall soil friction angle, wall height, the amplitude of horizontal and vertical seismic acceleration coefficient) on the seismic active failure angle, as well as the seismic active earth pressure and its coefficient are discussed. In addition, the seismic active earth pressure and its coefficients calculated by the proposed method are compared with the existing pseudo-static and pseudo-dynamic methods. The results show that: The seismic active failure angle, the seismic active earth pressure and its coefficient change periodically with time, and the seismic active earth pressure distribution along the wall height is nonlinear. The seismic active earth pressure and its coefficient obtained by this method are larger than those obtained by the existing quasi-static method.