In order to further explore the influencing factors and laws of the film flow field at the outlet of the orifice of aerostatic bearing with shallow cavity,the physical model of the outlet of the orifice of the aerostatic bearing was established,and the NS equation of the film flow field area at the outlet of the orifice of aerostatic bearing was solved by using three models,i.e.Laminar model, k-ω model and k-εmodel.The effect of air film clearance and supply pressure on the film flow field at the outlet of the orifice of aerostatic bearing was analyzed.The results show that there was a sharp pressure depressing at the outlet of the orifice of the aerostatic bearing,especially at the interface between the shallow cavity and the clearance of the air film,which has a certain impact on the precision and stability of precision motion mechanism and precision measuring equipment.The calculation results of the three models are consistent,and the numerical results of the Laminal model and the k-ω model are closer.With the increase of air film clearance and supply pressure,the sharp depressing amplitude of the pressure and the sharp rise amplitude of the Mach number at the outlet of the orifice of aerostatic bearing are increased.