The sheet-pile retaining structure with rigid load-relieving component is the good structural type of high-pile wharf in land-based connection in deep thick soft soil area. In order to reach the conclusion of the stress and deformation characteristics between before and after piles under the conditions of different piles row distance, back row pile spacing and excavation depth, and to do a deep study on the distribution of internal force before and after piles under the unloading cap, the results show that to increase the spacing between two rows of pile foundation can reduce the horizontal deformation, and the back-row pile stress distribution more reasonable; change the back pile spacing allows the front pile horizontal and vertical displacement are gradually increasing, and pile end bending moment and shear force are increased; the excavation depth increases the structural horizontal displacement increase.