Abstract: A switch device includes a holder (2), an operation knob (3) that has a display and is held in the holder so as to be movable forward and rearward, a ring-like coil antenna (15), a circuit board (7) on which a detection means for detecting the operation of the operation knob is disposed, LEDs (light source) that are disposed on the circuit board and illuminate the display on the operation knob, and a slider (5) that is stored in the holder 2 so as to be movable forward and rearward integrally with the operation knob and has light guide paths for the LEDs, a center axis of the coil antenna is offset from an operational center line of the operation knob, and the light guide paths of the slider and the display on the operation knob are disposed opposed to a center hole of the coil antenna.