A stage device comprises an XY-stage movable two-dimensionally in a predetermined reference plane, a Z-stage provided on the XY-stage and capable of a vernier movement in a Z-direction substantially perpendicular to said reference plane, and a levelling stage provided on the Z-stage and capable of an arbitrary inclining movement with respect to the reference plane. There is also provided a laser interferometer for measuring the position of a stage base portion in the X- or Y-direction by projecting a light beam onto a mirror provided on the Z-stage, and the measuring axis of the interferometer is so selected as to be contained in the reference plane. The levelling stage can be inclined in an arbitrary direction with means for driving plural points of the levelling stage independently in the Z-direction. Further it is so designed that the moving points are approximately positioned on the reference plane when the driving points are in a predetermined neutral stage.