PURPOSE: To provide an operating current display device by which whether a cause to occurrence of a fault of the remote supervisory control system results from a rating over of the operating current of the remote supervisory control system or not is easily discriminated on the occurrence of a fault in the remote supervisory control system.

CONSTITUTION: A voltage amplifier circuit 1 is connected to a secondary winding of a current transformer CT using one of transmission lines Ls for a primary winding. An output voltage of the voltage amplifier circuit 1 is converted into a digital value by an A/D converter circuit 2. A control circuit 3 generates display data to display a current flowing to the transmission line Ls based on data outputted from the A/D converter circuit 2. A display element drive circuit 4 drives a display element 5 based on display data sent from the control circuit 3 to display digitally a current (operating current) flowing through the transmission line Ls. On the occurrence of a fault in the system, whether or not the cause results from an over rating current is easily recognized.