Abstract: Based on the theory of vehicle-track coupling dynamics, a model of vehicle-track coupling vibration is established, in which a rail is assumed to be a Timoshenko beam resting on the discrete sleepers. The natural vibrations of tracks are analyzed, and dynamic responses between vehicle and track caused by track irregularity are also preliminarily investigated. The characteristics of the natural vibration and forced vibration of the Timoshenko beam model are different from those of Bernoulli-Euler beam model. It is shown that the Timoshenko beam model is more applicable to describing the high-frequency vibration of rails.