The invention relates to a switch and a GIS switch device. The GIS switch device comprises a shell and the switch in the shell. The switch comprises a moving end component with a moving contact and a fixed end component with a fixed contact. The switch also comprises a magnetic control detection device for detecting the moving contact and the fixed contact. The magnetic control detection device comprises a magnetic control switch and a magnetic force triggering component. The magnetic control switch is arranged on the fixed end component, and the magnetic force triggering component is arranged on the moving end component, or the magnetic control switch is arranged on the moving end component and the magnetic force triggering component is arranged on the fixed end component. Compared with a traditional mechanical travel switch, the switch and the GIS switch device have the advantages that the magnetic control switch is not mechanically impacted, is not liable to damage and has longer service life and low overhaul frequency, and the switch state detection is realized in a magnetic field sensing mode, and for the condition that a leaf spring of the travel switch and the contacts cannot be closed due to the fact that the moving contact forms deviation, a threshold value of the electric field intensity sensed by the magnetic control switch is wider, so the detection is more accurate.