In this chapter, the dynamic behavior of the train-slab track-subgrade coupling system is analyzed by using the vehicle and track element model and algorithm. Parameter analyses are conducted on the stiffness and damping of the rail fastening system, the CA mortar layer, and the subgrade. The results indicate that, among the six parameters considered, the stiffness of the rail fastening system and the subgrade have the most significant influence on the dynamic response of both the train and the track structure. Increasing the stiffness of the rail pad and fasteners helps mitigate wheel-rail interaction, whereas reducing their stiffness aids in attenuating vibrations in the track foundation. Additionally, lower subgrade stiffness may result in considerable dynamic responses within the track structure. Therefore, selecting appropriate stiffness values for the rail pad and fasteners, along with increasing the subgrade stiffness, is essential to ensure the safe and stable operation of the track system. The findings from the parameter analysis provide valuable guidance for optimizing the structural parameters of the slab track and supporting the design of track structures.