To investigate the variation characteristics of gear time-varying mesh stiffness under asperity-dominated contact, utilizing the geometric relationship formula for double-tooth engagement and surface topography, the fractal theory was employed to describe the gear profile. The W-M function was used to calculate and analyze the influence of different fractal dimensions on the time-varying meshing stiffness of gears. The results indicate that: As the fractal dimension increases, the fluctuation of time-varying meshing stiffness decreases, and the system tends toward more stable periodic motion.