Abstract: A gas insulated bus includes: a first container including a first flange and forming a sealed space in which an insulating gas is enclosed; a second container including a second flange joined to the first flange and forming the sealed space together with the first container; a conductor housed in the sealed space; and an insulating support supporting the conductor in the sealed space. Part of the second flange is an inner flange including a mounting to which the insulating support is attached. The second container includes an extension portion in a portion in which the inner flange is provided, the extension portion extending toward a side opposite to a central axis of the conductor.