Abstract: For most researches on the seismic stability of retaining walls, the embedment depth of the wall is often assumed to be zero, resulting in the role of backfill in front of the wall being neglected. Based on the theory of the upper bound limit analysis, the impact of embedment depth on the seismic stability of retaining walls with cohesive backfill is investigated. The diagonal slice method is employed to differentiate the backfill in front of and behind the wall into rigid soil slices parallel to the rupture surface. A wall-soil system in which the retaining wall rotates around the toe of the wall and the fill in front of and behind the wall slides in pieces is established. According to the work-energy balance equation, the expression for the seismic acceleration coefficient of the retaining wall is derived, and the effects of filling height, internal friction angle, filling cohesion and wall-soil friction angle on the seismic rotational stability of the retaining wall under seismic action are discussed. The results show that when the ratio of the height of backfill in front of the wall to the height of backfill behind the wall (H₂/H₁) is greater than 0.15, the coefficient of seismic yield acceleration will increase dramatically, and the seismic stability of the retaining wall will be underestimated if the effects of backfill in front of the wall are neglected at this time. Finally, the accuracy of the proposed method is confirmed by comparing with the method of the limit equilibrium theory.