In order to study the anti-seepage design scheme of a large sluice in deep sandy soil foundation,AutoBank software and MIDAS finite element software were used to calculate and analyze the seepage and stress deformation.The research shows that when there is no cutoff wall or suspended cutoff wall,the maximum slope of the outlet section of the sluice foundation is less than the allowable slope of the outlet section,while the maximum slope of the horizontal section is greater than the allowable slope of the horizontal section and the leakage is large.The upper part of the cutoff wall is mainly tensile stress,but it does not exceed the design tensile strength of concrete.The middle and lower part of the cutoff wall is dominated by compressive stress,and the maximum compressive stress appears at the stratum boundary,but it does not exceed the design compressive strength of concrete.The stress distribution of ordinary concrete cutoff wall and plastic concrete cutoff wall is quite different in the upper area near the stratum boundary and the bottom embedded end.The maximum tensile stress of the ordinary concrete cutoff wall in the upper part of the stratum boundary is 0.37 MPa,and the maximum tensile stress value of the bottom embedded end is 1.46 MPa,which exceeds the design tensile strength of the concrete.The plastic concrete cutoff wall has no tensile stress at the above parts.The horizontal displacements of ordinary concrete cutoff wall and plastic concrete cutoff wall are basically the same,but because of the low elastic modulus of plastic concrete cutoff wall,the vertical displacement of plastic concrete cutoff wall is larger than that of ordinary concrete cutoff wall.