By using the finite element software ABAQUS,a three dimensions model is established which considers interaction between the caisson and the foundation.Besides,this paper simulates caisson wharf rear pressure distribution under the action of gravity.The result shows that stiffness difference in the direction along the wharf length is caused by the caisson cell and cell backfill in each section,and caisson rear earth pressure distribution appears relatively obvious space characteristic,in the meantime the total force is larger than the calculated value by design codes,which makes the stability of the structure is less securable.Combining with simulation results of engineering examples,a practical and reasonable calculation model of the rear earth pressure is proposed.