Gate valve

A gate valve according to the present invention comprises: a valve housing having a first opening and a second opening; the valve body is positioned in the hollow part in the valve box; a rotating shaft supporting the valve body; a rotation drive unit for rotatably driving the valve body; a neutral valve part connecting the valve body to the rotating shaft; a movable valve frame section provided to the valve body; a valve frame biasing part connecting the neutral valve part and the movable valve frame part; a movable valve plate section that is provided to the valve body and that is displaceable in the flow path direction by the valve plate sliding seal section with respect to the movable valve frame section; the valve plate force application part is connected with the movable valve frame part and the movable valve plate part; a valve box urging part capable of moving the movable valve frame part towards a valve closing position in contact with the periphery of the first opening part; and a drive unit for dri