Provided is an SPDT switch having improved isolation characteristics in an RF band. The SPDT switch includes a serial switching unit, a current sink unit, a switching isolation unit, and a DC blocking unit. The serial switching unit includes first and second HBTs. The current sink unit sinks a current flowing from a common input terminal to each of first and second output terminals of the serial switching unit. The switching isolation unit causes an unselected output terminal of the first and second output terminals to be electrically isolated from the common input terminal when the serial switching unit operates. The DC blocking unit blocks a DC between the first HBT and the first output terminal and a DC between the second HBT and the second output terminal. Accordingly, it is possible to provide better insertion-loss and isolation characteristics in higher frequency bands than typical switches.