The key factors causing the vehicle vibration or derailment is the complex wheel/rail contact relationship and variable crosssections characteristics when the vehicle passing through the turnout .According to the design and disposition of the Chinese 60kg/m rail NO.18 turnout with movablenose, a vehicleturnout coupling model is built up in the multibody dynamics analysis software. The dynamics model is verified. The dynamics responses are calculated when the vehicle passing through the turnout on the divergent route and the major track respectively. The results show that the major effects on the dynamics parameters of the vehicle are the cross section variation in switch and frog and the geometrical contact between wheels and rails. At last, the effect of the integral stiffness and damping of the track on the dynamics performance of the vehicle system is discussed based on the dynamics response analysis aiming at the optimal vehicle security, stability and comfort and providing a reference for the matching scheme of the subrail stiffness and damping parameters with the discrete the track model.