The invention discloses a two-freedom-degree linear type fast tool servo device based on an aerostatic guide rail. The two-freedom-degree linear type fast tool servo device comprises an outer shell, Z-direction drive and X-direction drive. The Z-direction drive is connected with the X-direction drive through a bolt to from a serial mechanism. Piezoelectric driving devices are adopted in the driving way of the Z-direction drive and the X-direction drive. Aerostatic guide rail guiding is adopted in the guiding way of the Z-direction drive and the X-direction drive. A diamond cutter is installed on the Z-direction drive, and high frequency linear type reciprocating servo movement of the diamond cutter in the X direction and Z direction is achieved. According to the two-freedom-degree linear type fast tool servo device based on the aerostatic guide rail, owing to non-contacting drive, the whole device is long in service life, and meanwhile, the high moving precision is achieved.