Abstract: With the rapid development of urban construction, precast piles are widely used in engineering because of its good performance. An indoor model experiment and finite element simulation that based on large deformation method were taken to study the change of the stress field andpore pressure in soil around pile. It is found that during the precast pile sinking process, under the same depth, the farther it is from the axial of pile, the smaller excessive pore water pressure of soil around pile, but the faster it dissipates, with the radius of influence of about 10 times pile diameter. There is similar law in depth direction. In pile sinking, radial extrusion remodeling around the pile mainly occurs within 1 time of pile diameter, with the influence range of displacement field at about 5 times pile diameter. During pile sinking, big sideway extrusion stress will be produced, with the influence range of stress field of about 7.5 times pile diameter.