Based on the case of a deep soft soil foundation pit project in the Pearl River Delta region, this paper optimizes the method of row piles into the rock, and explores the effect of the row piles into the rock + skirt reinforced support method on the foundation pit deformation. A representative section in the middle of the foundation pit was selected, and a three-dimensional calculation model was established by using MIDAS / GTS NX finite element software to compare the horizontal displacement of row piles, uplift of the pit bottom, surrounding surface settlement, engineering cost and construction difficulty. Piling without rock and proper skirt reinforcement can effectively reduce horizontal displacement of piles, uplift of pit bottom, and surrounding ground settlement. After the depth of reinforcement exceeds a certain range, the effect on reducing deformation of foundation pit is not obvious; The cost and construction difficulty of the optimization scheme project are similar to the original plan, which can provide reference for similar engineering design.