Abstract: The prestressed strut has a firm control over the deformation of foundation pit, but a consensus about the regularity of the influence on deformation of foundation pit which is induced by prestress of strut has not been obtained. In order to compare the effects of different prestress schemes, a two-dimensional finite difference software named FLAC is adopted to analyze the foundation pits where the struts is prestressed. By comparing the additional displacement and moment of the retaining wall induced by the prestress of different prestress schemes and on different stages in excavation, it is found that additional displacement and moment of the retaining wall induced by the prestress remains the same on different stages in excavation. The effect of the prestress in several struts functioning simultaneously is equal to the sum of effect of each prestress functioning alone and the additional displacement and moment of the retaining wall is proportional to the size of prestress. The effect on retaining wall induced by prestress is mainly controlled by its relative position to the retaining wall.