Abstract: ABAQUS software,a finite element method(FEM),was employed to study the behavior of deformated profiles of a horizontal cohesionless backfill against a vertical RC retaining wall simulated with translation mode.The Mohr-Coulomb failure criterion was taken as yielding function and the associated flow rules were used.Study was conducted regarding to the relationship between the lateral earth pressure,the acting point of resultant force and the resulting turning moment to the back of retaining walls,and the deformed ground profile of backfills.Relationships between the abrupt change area on the backfill ground and the sliding surface of traditional Coulomb’s theory were also compared and discussed.