Abstract: A projection exposure apparatus controls the position of a mask so that the mask is in a desired position without reducing throughput even if the size of the mask is increased. For example, a controller adjusts the pressure of air blown from air holes so that a reticle is floated at a desired distance above a reticle floating plate. The controller also controls the driving of linear motors having stators and sliders, thereby adjusting the pressing force of control bars in contact with the sides of the floating reticle to press the sides of the reticle and control the two-dimensional position of the reticle. Therefore, it is possible to control a mask so that the mask is placed in a desired position without reducing throughput.