The utility model discloses an earthing device for transformer core and folder current measurement is equipped with the ground connection flange on the shell of transformer, this earthing device includes: the insulating part, the fixed setting in the lumen of ground connection flange, it is first to have mutual spaced on the insulating part, second and the 3rd wiring pile, wherein, the inner of awiring pile is connected with transformer core's ground connection copper strips, the inner of the 2nd wiring pile is connected with clamp of transformer's ground connection copper strips, the 3rd wiring pile's inner ground connection, the dustcoat, flange seal is connected with ground connection, wear to be equipped with first and second on the dustcoat and measure the cable, wherein, the first and second measurement portions of mid portion for being used for electric current non -contact measurement outside the dustcoat that expose of measuring the cable. According to the utility model discloses an earthing device, utilize the non -contact measurement device direct to the first and second measurement portions of measuring cables measure can, need not contact and operation transformer core, folder and ground terminal, measure safely, quick.