Femtosecond laser is used to ablate a CaF2 crystal surface. By varying the laser parameters, we produce the microstructures (including ablation holes and lines) using stationary focusing ablation and dynamic scanning. The laser-induced microstructures on CaF2 crystal surface under both processing modes are investigated to obtain the parameter dependence and ablation threshold. The calculation results reveal that the incubation factor is 0.0033 in the stationary focusing case; whereas, in the case of dynamic scanning, the incubation factor is 0.0043 or 0.0052 when the scanning direction is perpendicular or parallel to the laser polarization, respectively. The results reveal that the incubation effect plays an important role in the process of femtosecond laser ablation on crystal surface.