Abstract: Due to the technological progress and good economic benefits, a large number of existing projects have adopted composite foundation. Because of the combined effects of piles and soils, the composite foundation can effectively reduce the deformation and lateral displacement of foundation. Based on the studies on the side pressures of composite foundation in sandy soil obtained by the centrifugal tests and finite element analysis models for sandy composite foundation, the ABAQUS finite element analysis models for composite foundation in clayey soils are established to analyze the influences of the additional loads, cohesive forces, internal friction angles and stiffnesses of retaining wall on the lateral pressures on the retaining wall, and the distribution of the lateral pressures along depth is obtained. The research is helpful to the effective design of supporting structures, to control the deformation of composite foundation and superstructure, and to save the cost of engineering projects.