There is provided a grounding switch-equipped gas insulation switch device in which a switch mechanism for opening/closing a main circuit and that for opening/closing grounding are made into a single compact body and a movable electrode for opening/closing grounding is rapidly operated by the switch mechanism. The grounding switch-equipped gas insulation switch device includes a sealing vessel for containing insulation gas, a main circuit switching fixed electrode (3) fixed tot he sealing vessel, a movable electrode (1) in contact with the main circuit switching fixed electrode (3), a grounding switching fixed electrode (4) capable of electrical connection, and a drive device for driving the movable electrode (1), thereby driving the movable electrode (1). The main circuit switching fixed electrode (3) and the grounding switching fixed electrode (4) are arranged in a rectilinear shape in the longitudinal direction of the movable electrode (1). The drive device drives and holds the movable electrode (1) in three positions: a closed position, an open position, and a grounding position in a rectilinear shape.