The drive screw was simplified as a rotating Timoshenko beam bearing the pre-tension force and moving forces, and the frequency equation of the screw with the elastic end supports was derived under considering the effect of gyroscope, the pre-tension force，the moving forces on the screw vibration, and the bearing stiffness. The dynamic model of the drive screw was established using Lagrange equation, and was analyzed adopting the mode superposition and Runge-Kutta method to calculate the transient response. Eventually, the effect of the system parameters on the whirl speed and lateral vibration was studied to supply a base for designing the drive system.