The piezoelectric thin film differential throttling valve which can realize the pressure of the oil outlet differential control is proposed. The mathematical model of the valve is established to obtain the flow equation. The dynamic model of the hydrostatic spindle whoese front end is supported by hydrostatic bearing and back end is supported by rolling bearing. The oil film force and flow formula of the hydrostatic bearing is obtained overlooking the hydrodynamic action of the hydrostatic bearing. In order to obtain the hydrostatic spindle axis trajectory expected,the contraposition recesses of the hydrostatic bearing are connected to the two oil outlets of the valve. The spindle axis trajectory can be controlled by controlling the piezoelectract. Finally,the relationship between the hydrostatic spindle axis trajectory expected and the displacement of the piezoelectric is simulated and the the relationship between the initial throttle clearance and the displacement of the piezoelectric is obtained.
