A windshield for a balance which has a door that can be automatically opened and closed or half opened and half closed is provided. The windshield includes doors to which air cylinders are joined as driving means, sensors for monitoring movements of the doors, pressure sensors configured to monitor a pressure of air to be supplied to the air cylinders of the driving means, and a control unit configured to stop an air supply to the air cylinders when a pressure of air monitored by the pressure sensor exceeds a predetermined value. Stoppers are disposed on movement paths of the doors to block movement, and when air pressure inside the air cylinder increases to the predetermined value due to contact with the stopper, the door stops. The door can be freely fully opened and half-opened according to the position of the stopper.