Femtosecond laser microcorrection technology is a new type of processing method that uses a laser with ultrashort pulse-width and high energy density to micromachine the gear tooth surface. Considering the mutual temperature induction between the components of the gear material, a kinetic energy thermal model of the femtosecond laser-ablated surface gear material was established, and the evolution of the temperature field of the tooth surface of the femtosecond laser-modified surface gear was simulated and analyzed. The temperature of electrons rises sharply and is much greater than the lattice temperature and the depth and diameter of ablation pits increase. The tooth surface morphology of the ablated pits was experimentally observed, confirming the correctness of the kinetic energy thermal model, and providing theoretical guidance for the study of femtosecond laser-ablated surface gears.