Abstract: Based on the classical plane strain assumption, considering the soils as a series of independent thin layers, the frequency-domain horizontal dynamic response of a cast-in-situ large-diameter concrete pipe pile in saturated soils is investigated. The potential functions are employed to decouple the consolidation equations of the soils, the analytical solutions of the outer and inner soils in frequency domain are obtained by the Laplace transform technique and the separation of variables. Under the assumption of perfect contacts between the pile and both the outer and inner soils, the response of the pile is derived and its complex impedances are obtained. The derived solution is compared with that of a solid pile to verify the rationality, and the difference between the two solutions is illustrated. The effects of the pile length and section radius on the complex impedance of pile top are analyzed.