The utility model discloses a GIS current transformer secondary lead wire backup pad department uses superfrequency sensor, including a sensor body, it has the antenna to inlay in the sensor body left end face, sensor body left end sets up the flange, set up the pilot hole on the flange, sensor body lower part sets up N type terminal and circular connector, the inside right side of sensor body sets up processing circuit, processing circuit includes signal connection's wave detector, amplifier and data processing unit in proper order, N type terminal with circular connector all with amplifier signal connects. The utility model discloses it is difficult to use the problem in GIS equipment CT secondary lead wire backup pad department effectively to have solved the superfrequency sensor.