In order to improve the climbing ability of rack vehicles， the gear-rack system is added to the traditional rail vehicles. Aiming at the problem that there are many kinds of gear-rack systems in the world at present， and the diversity of gear-rack sys? tems equipped with them leading to the dynamic characteristics difference of rack vehicles， this paper considers the impact of gearrack meshing on the basis of analyzing the generation mechanism of gear-rack meshing excitation， the rack vehicle coupled dynamic models with two kinds of Strub system， double row teeth Abt system and Locher system are established， and experimental verifi? cation on the model are carried out； Based on the model， the gear-rack meshing behavior of rack vehicle running at different speeds on the engagement section of the ramp is analyzed， and the influence of track irregularities on the gear-rack meshing center distance error is explored； On this basis， the wheel/rail action and car body acceleration of the rack vehicle are studied， and the rack vehicle safety are analyzed as well as stabitity. The results show that there are significant differences in the dynamic characteristics of rack vehicles with different gear-rack systems， and the Locher system has the best dynamic characteristics； The gear-rack meshing be? havior of coaxial Strub system and double row teeth Abt system is poor and affected by the track irregularity obviously. The maxi? mum impact value of the gear-rack contact force is 20.3 kN， and the meshing center distance error is 3.73 cm； The safety of coaxial Strub system and double row teeth Abt system is poor， and the maximum wheel/rail vertical force of double row teeth Abt system is 51.7 kN； The car body stability of the differential shaft Strub system is the worst. The maximum car body acceleration is 0.033 m/s2 ， and the stability index is 1.27. The conclusions offer theoretical support for the design， safe operation， and mainte? nance of mountain rack railways in China.