To reduce the vertical vibration of the rail in the frequency range of 500-2000 Hz, a vehicle-track vertical coupled vibration model including a rail composite vibration absorber was established. The vibration response of the rail at each typical position in the coupled model and the orbit model is compared, and the importance of the coupled model is illustrated. According to the two evaluation indexes of the vibration response at the peak frequency and the root mean square value in the frequency band, the limitations of the single-degree-of-freedom vibration absorber are pointed out, and the general steps of the parameter design of the composite vibration absorber are proposed. The design of the design section is evaluated by the vibration attenuation rate, which verifies the effectiveness of the design method. The results show that considering the influence of the vehicle, the peak value of the vertical vibration energy of the rail will shift, and the increase of the vehicle speed will aggravate the vibration response. Under the same total mass, the single-degree-of-freedom vibration absorber has good vibration damping for a certain frequency, and in a wider frequency band, the composite vibration absorber can achieve better vibration damping effect. For the parameter design of the composite vibration absorber, the optimal design frequency of the vibration absorber is obtained by determining the main influence parameters and using the genetic algorithm to perform numerical optimization. The work of the thesis provides an important reference for the research of rail composite vibration absorbers.