A field device includes: a current controller configured to operate with a first power supply voltage and output a control signal for controlling a current to be output to a transmission line; a current output unit configured to operate with a second power supply voltage different from the first power supply voltage, the current output unit being capable of outputting a current of a magnitude corresponding to the control signal output from the current controller to the transmission line; and an abnormality notification unit configured to output, to the current output unit, a first signal for causing the current output unit to output a burnout current indicating that an abnormality has occurred in a case in which an abnormality occurs in the first power supply voltage.