Abstract: The primary concern in large-scale marine reclamation project is the settlement of the filling soil itself. In addition, the deformation of the marine sedimentary underlayer and its pulling effect on upper filling soil cannot be ignored. Based on an in-situ load test, we studied the friction distribution, end resistance and load-deformation characteristics of piles in reclamation engineering. Through numerical simulation, the pile’s skin friction and axial force under the long-term ground deformation were obtained. The results showed that the underlying layer deformation had a great influence on the long-term working characteristics of pile foundation, especially the soil layer in which positive friction on pile surface changing into negative friction, and the larger the positive friction, the greater the negative friction would be generated after ground deformation. The results of in-situ pile test could not be the only reference for pile design, more attention should be paid on long term stability of foundation.