A switch device capable of preventing an occurrence of contact noise and wobbling of a stabilizer member to a bearing is provided. The key switch includes the stabilizer member supported between a key top and a base plate. The stabilizer member includes a first shaft portion rotatably supported on the lower surface side of the key top and a second shaft portion, which has a rotation axis parallel to the rotation axis of the first shaft portion and is rotatably supported by a bearing provided on the upper surface side of the base plate. The membrane sheet has at least a lower contact sheet having a cut-out shaped portion in a position corresponding to a position in which the second shaft portion is provided in a plane view and an upper contact sheet placed in an upper layer than the lower contact sheet to cover the cut-out shaped portion.