Abstract: The dynamic response of pile foundations in saturated sand was explored through the shake table test. Some ideas about dynamic soil-pile interaction during strong shaking were obtained. Based on the results of the experiment, it is demonstrated that the bending moment of the pile decreases with the increase of the pore pressure in sand. And the conclusion is presented that the amplitude of the vibrating pore pressure at different depth is related to the amplitude of the bending moment of pile at the corresponding depth.