A capacitive switch includes: a first conductive cantilever, a second conductive cantilever, a substrate, a coplanar waveguide arranged on the substrate, the coplanar waveguide includes a first conductor configured to transmit an electrical signal, a second conductor and a third conductor are arranged as ground wires on two sides of the first conductor; an insulation medium layer is arranged on the first conductor, a conducting layer is arranged on the insulation medium layer; the first conductive cantilever is connected to the second conductor by using a first fixed end, the second conductive cantilever is connected to the third conductor by using a second fixed end; when a direct-current signal is transmitted on the capacitive switch, a first free end of the first conductive cantilever and a second free end of the second conductive cantilever contact the conducting layer.