Abstract: Based on the engineering practice about the pile-soil penetration interaction of Shengli No.5 Jack-up in Bohai Bay, a numerical model for the pile-soil penetration process is established to investigate the bearing capacity of an optimized spudcan structure which is then compared to that of the real spudcan. The results show that the spudcan bearing capacity first increases and then decreases from inside to outside along the radial and vertical optimized position.At the radial r'/r=0.6 position and vertical h/H=0.4 position, the optimized structure satisfies expectation.It is concluded that the supports in reasonable positions can increase the spudcan bearing capacity and maintain the stability of the penetration process by changing the flow mechanism of soil, which decreases the impulse and velocity deficit of the soil at the top and bottom of the spudcan.