The soil pressure is the main load imposing on the steel cylindrical structure,and it is very important for analyzing the interaction mechanism between cylindrical structure and soil.Based on the west artificial island of the island and tunnel project of Hong Kong-Zhuhai-Macao Bridge,we apply the finite element software PLAXIS 3D to establish the whole spatial elastoplastic finite element model of the deep-buried large-diameter steel cylindrical island wall structure,analyze passive soil pressure distribution curve in front of the steel cylinder and the vertical soil pressure distribution curve at the bottom of the steel cylinder,and compare the soil pressure curves with the 2D equivalent calculation method and the classical Rankine and Coulomb soil pressure theories under the same conditions.The results show that the passive soil pressure value in front of the steel cylinder structure using 3D numerical simulation method is the lowest,and the tendency of increasing with depth is consistent with the classical theories.The vertical soil pressure at the bottom of the cylinder using 3D numerical simulation method is basically consistent with the trend and value of the 2D equivalent calculation results.