Abstract: The spring-compensated double-split anti-backlash gear suppresses the reversing idle travel caused by gear backlash by optimizing the pre-torsion moment of the torsional spring and gear parameters, so as to improve the transmission accuracy and meshing stiffness of the system. It is of great significance to investigate its dynamic meshing characteristics. To properly select the parameters of anti-backlash gears and enhance the meshing stiffness between tooth surfaces, a comprehensive meshing stiffness model for spring-compensated double-split anti-backlash gears is established based on the Hertz contact theory in this paper. Taking the structural parameters of the spring-compensated double-split anti-backlash gear for a certain side-stick as a numerical example, the influence laws of torsional spring stiffness and gear structural parameters on the comprehensive meshing stiffness are studied. The results show that, under the meshing condition that the driving and driven gears keep continuous contact without transient separation, the double-split anti-backlash gear mechanism can eliminate the interruption effect of gear backlash on tooth contact and improve the transmission accuracy of the transmission system. Without replacing high-strength gear materials, the anti-vibration performance and comprehensive meshing stiffness of the mechanical transmission mechanism can be improved by optimizing gear and torsional spring parameters.