Abstract: During the foundation excavations in the deep thick soft soil area, the soft soil at the bottom of the foundation is stirred and strengthened to form a high-strength floor to ensure the stability. The side wall is supported by supporting piles to avoid the side wall from collapsing. The ship-form structural support system formed by the combination of the supporting piles and reinforced bottom plates is similar to the ship's side wall and bottom plate to ensure the stability of the foundation excavation. Combining with specific engineering examples, the design method of the side wall and bottom plate of ship-form retaining are introduced. The successful implementation of the engineering case and the monitoring results show that the ship-form retaining can not only avoid the excessively deep embedding of the support piles, but also facilitate the earthwork construction of the soft soil and the protection of the engineering piles. It is safe and reliable. It has certain reference significance for similar projects.