Combined with the example of the East Artificial Island of the Hong Kong-Zhuhai-Macao Bridge Island Tunnel Project,based on the PLAXIS 3D finite element software calculation platform and the Hardening-soil model,which can consider both shear hardening and compression hardening,the 3D numerical calculation of the deep-inserted large diameter steel cylinder island wall structure is studied,and the displacement of the steel cylinder under various control conditions in the whole construction process is analyzed.The deformation and stability characteristics of large cylinder structure on deep soft clay foundation are discussed,which are verified by 2D theoretical calculation and field displacement measurements.The results show that the displacement of the steel cylinder in 3D numerical simulation is similar to the measured displacement,both of which are larger than the equivalent displacement in 2D plane.When the steel cylinder has enough diameter and buried depth,even if it is inserted into deep soft clay foundation,the horizontal and vertical displacement are larger,but its structural stability is also better.The analysis results have certain reference significance for similar projects and the popularization and application of large diameter steel cylinder structure in soft soil foundation.