A stage device including a base plate which includes a reference surface, a stage which can move along the reference surface, a mass body which can move with respect to the base plate or a structure of the base plate, and a control unit which drives and controls the mass body so as to cancel a reaction force in a translational direction generated during a movement of the stage and an offset load about a horizontal axis, and to reduce a rotational reaction force about a vertical axis. The control unit includes a mass body model control unit which generates a virtual control target value of the mass body to cancel the rotational reaction force about the horizontal axis generated during the movement of the stage, on the basis of target position information of the stage, and a mass body model based on the virtual control target value. The control unit drives and controls the mass body by using virtual positional information of the mass body model as an actual mass body control target value.