Based on analysis of magnetic febric and magnetic relict, the paleocurrents recorded in drilling cores in Subei coastal plain are bidirectional. NE_SW in the northern core and NW_SE in the southern core. The paleocurrent pattern in the area is similar to that of the tidal current system in the South Yellow Sea. So it is inferred that the convergent_divergent tidal current system existed during stage of sand body formation, and they should be radial in plane. Based on analysis of magnetic febric and magnetic relict, the paleocurrents recorded in drilling cores in Subei coastal plain are bidirectional. NE_SW in the northern core and NW_SE in the southern core. The paleocurrent pattern in the area is similar to that of the tidal current system in the South Yellow Sea. So it is inferred that the convergent_divergent tidal current system existed during stage of sand body formation, and that they should be radial in plane.