Abstract: A slide gate includes a frame fixed to a bottom of a molten-steel vessel, a guide frame attached to a bottom of the frame which can opened and closed, a plurality of refractory plates, a pair of surface-pressure bars and a cylinder. The plurality of refractory plates are disposed in a space surrounded by the frame and the guide frame with one of the refractory plates being slidable to control an amount of opening of a nozzle gate. The cylinder drives the slidable refractory plate to move a slide block with a protrusion. The protrusion moves a connecting member of the pair of surface-pressure bars so that the guide frame is connected with the frame and the slidable refractory plate is pressed to an immediate upper refractory plate by coil spring.