Abstract: The soil under the pipe pile is regarded as virtual soil pipe pile and the torsional dynamic interaction between the pipe pile and the soil around pile and the pile core soil are equivalent to the dynamic torsional Winkler spring-damper, the torsional dynamic model of partially exposed friction pipe pile is established. Considering the boundary conditions of soil layer, the torsional action of soil around pile and pile core soil on pipe pile is obtained by solving Bessel equation, and the stiffness coefficient and damping coefficient of dynamic torsional Winkler spring-damper are obtained. Considering the continuity boundary conditions of the virtual soil pipe pile, the embedded partial pipe pile and the exposed partial pipe pile, the torsional complex stiffness at the top of the partially exposed friction pipe pile is obtained by using the initial parameter method and the transfer matrix method. The effects of geometric parameters and physical parameters of pipe pile and the soil physical parameters on the torsional complex stiffness of partially exposed friction pipe piles are analyzed and discussed by numerical examples. The results show that the thickness of soil layer under pipe pile has little effect on the torsional complex stiffness of partly exposed friction pipe pile. When the length of embedded partial pipe pile reaches a certain degree, the restriction conditions at the bottom of pipe pile have little effect on the torsional vibration of pipe pile. The length of embedded partial pipe pile and the length of exposed partial pipe pile have great influence on torsional vibration of partly exposed friction pipe pile. The stability of pipe pile is unfavorable when the wall of pipe pile is too thin or the shear modulus of pile core soil is too small. Increasing the shear modulus of the soil corresponding to the embedded partial pipe pile is beneficial to the stability of the partly exposed friction pipe pile.