Provided is a switching device including: a cascode switch including at least two transistors connected in series and receiving a switching control signal; and a third switch receiving the switching control signal, wherein the at least two transistors include a first transistor receiving the switching control signal through a control terminal and a second transistor having a control terminal connected to a first voltage source, and wherein the third switch is connected between the control terminal and the first terminal of the second transistor, is turned off when the first transistor is turned on, and is turned on when the first transistor is turned off.