To provide a reliable switch, a push button switch, and a rotary switch in which a movable contact piece itself is provided with a spring function that elastically restores in conjunction with switching operation as well as an intrinsic contact function of the movable contact piece, for the reduced number of components and lower cost while good contact is assured.

A contact switch mechanism is provided with a U-shape movable contact piece which is supported for free tilting while energized to contact a fixed contact piece side. The movable contact piece contacts are switched by inverting, in a see-saw, the movable contact piece while the tilting support part for the movable contact piece is made to contact to a common fixed contact piece side at all times.