Taking the dynamichydrostatic hybrid gas bearings with orifice restrictors and deepshallow cavities as the research object,the load characteristics were analyzed by Fluent software.The influences of eccentricity,supply pressure,spindle speed,airfilm thickness and shallow cavity depth ratio on bearing capacity and stiffness were studied.The results show that the average pressure in the shallow cavity of the dynamichydrostatic hybrid gas bearings with orifice restrictors and deepshallow cavities is greater than that in the deep cavity,and the maximum pressure area occurs at the end of the shallow cavity near the bearing end.With the increase of the supply pressure,the bearing capacity is increased gradually,but the supply pressure should not exceed 0.95 MPa.When the spindle speed is within 3×10.5 r/min,the bearing capacity and stiffness are increased linearly with the increase of spindle speed.When the spindle speed exceeds 3×10.5 r/min,the growth trend of bearing capacity and stiffness slows down obviously.As the shallow cavity depth ratio increases,the bearing capacity and stiffness are increased first and then decreased.When the depth of the shallow cavity is 1 to 1.5 times the thickness of the gas film,the bearing capacity and stiffness are close to the maximum.