The stiffness transition section of high-speed railway CRTSⅢ slab ballastless track in vibration damping section and non vibration damping section is studiedin this paper. Based on the vehicle track coupling dynamic simulation analysis, the influence of each transition length and transition stage on the dynamic response of wheel rail is discussed under the condition that the stiffness of damping pad in each transition section decreases by double.The research results show that: when the transition stage is determined, the length of three track plates (about 15 m) is used for each transition stage, the wheel rail force amplitude, the difference of the downward pressure of fasteners on both sides of the panel seam at the junction of the transition section and the vibration damping section, the vertical and lateral acceleration amplitude of the car body, the derailment coefficient and the wheel rail load reduction rate are the minimum, and the rail deflection rate, the train running quality and stability meet the relevant limit requirements ;When the transition length of each stage is determined, the transition stages are three, the sudden change value of vertical displacement of wheelset, the amplitude of wheel rail force, the amplitude of rail deflection rate, the downward pressure of fasteners on both sides of slab gap, the staggering amount on both sides of slab gap at the junction of transition section and non damping section and the difference of downward pressure of fasteners are the minimum, and the rail deflection rate, train running quality and stability meet the requirements of relevant limit values within the scope of the transition section, the train has a larger wheel rail impact when passing through the rail joint, especially at the interface of the transition sections at all levels. The wheel rail impact is more significant. It is recommended to strengthen the maintenance of the fastening system near the interface of the plate and the transition sections.