Abstract: To quantitatively analyze the expansion and shrinkage deformation of the expansive soil and laterite under wet and dry cycles, a series experiments were conducted, including the confined lateral expansion and the allowed lateral contraction tests on compacted soils under wet and dry cycles with different overlying load. It demonstrated that under same times of wet and dry cycles, the deformation of expansive soil and laterite samples amplitude decreases with the increase of the overlying load. And the effect of overlying load can restrain the expansion and shrinkage deformation of the expansive soil at different degrees.