Femtosecond laser micromachining is a manufacturing method that uses ultra-short pulse width and ultra-high energy laser to accurately remove materials. In this paper, considering the mutual temperature induction among the components of the face gear material 18Cr2Ni4WA, the energy coupling model of femtosecond laser ablation of face gear material is established, and the change process of electron temperature and lattice temperature under different energy densities is simulated and analyzed. The results show that electron temperature increases rapidly with the increase of laser energy density and is much higher than the lattice temperature. The laser with energy of 0.320-5.255 J/cm² is used to observe the ablation morphology of face gear tooth surface and detect the tooth surface roughness. The results show that the ablation morphology is smooth and the minimumroughness is 0.265 μm, which is basically consistent with the simulation analysis results of the energy coupling model, and provide a basis for improving the research of face gear surface quality.