Based on the thought of the system engineering theory,the questions about the dynamic characteristics of vehicle-track coupling system on curved track and the vibration response of ballastless track structure of passenger traffic railway are analyzed and are simulated research.The main searches are as follows:(1) Depending on the theory of vehicle-track coupling dynamic and finite element method,the motion state of each part of the vehicle-track coupling system is analyzed in particular.The dynamic models of vehicle structure,curve ballasted track structure,ballastless track structure are built separately.The rail/wheel contact model adopting FEM to calculate the rolling contact progress is brought forward.LM worn profiled wheel tread is adopted.Each part of the track structure model is built by real size and relation,and is simplified appropriately.The calculation about rail/wheel contact interaction is close to real status.The wheel can roll on the track,or glide relative to track,or separate from track.Thus,the phenomena of the vehicle’ climb on rail and derail are simulated. Through applying the wheel rotate velocity,the forward rolling of the wheel is realized,and then it is true more than giving a vehicle velocity.(2) Adopting ABAQUS software,the vehicle-track coupling system of Passenger Traffic Railway is simulated research.Explicit method and the contact penalty function method are used for calculation.In the contact calculation,constraint enforcement methods is described the pressure-overclosure behavior,contact surface weighting method & tracking approach are used to judged contact state,contact tangent action is described by corresponding sliding formulation.The calculate results show that adopting FEM to calculated rolling contact progress is feasible and the results is more exact.(3) Taking example by the engineering of rail traffic in a city,the dynamic characteristics of the vehicle-track coupling systems of ballasted track and ballastless track are simulated respectively.By contrasting the simu