To provide a switching device capable of turning on or turning off power feeding to a 100V receptacle of a 200V receptacle, without operating a breaker.

The switching device 2 is provided with an input section 6, equipped with three input terminals 6a to 6c for a three-wire 5 single-phase three-wire system to be connected to; an output section 7 equipped with output terminals 7a1 to 7b2 outputting 100V and 200V, respectively, obtained by the three-wire single-phase three-wire 5 system connected to the input terminals 3a to 3c of the input section 6; and a switching section 8, connected between the input section 6 and the output section 7 for turning on or off the outputs of 100V and 200V from the output section 7, at the same time.