PURPOSE: To connect the earth for an electric welding device in a single operation by copper-plating the surface of a strong permanent magnet with a hole, fixing an earth electrode, which made of iron, and an upper frame together by a nut, welding a screw on the earth electrode, copper-plating the whole surface of the earth electrode and the welded screw, and inserting an earth cable into an earth cable mounting part to be fixed by a bolt.

CONSTITUTION: The surface of a strong permanent magnet with a hole 9 is copper-plated, and an earth electrode 10 and an upper frame 13 are fixed to each other by a nut 17. A screw 11 is welded 12 to the earth electrode 10, which is made of iron and is provided with projection parts and recessed parts on its bottom face, and the whole surface of this component is copper-plated. In the upper frame 13, a removing handle 14 is spot-welded, and an earth cable 18 is inserted into an earth cable mounting part 15 to be fixed by a bolt 16. The earth electrode 10 is turned into a magnet via the magnet or iron, so that the earth of an electric welding device can be connected in a single operation. In addition, the earth can be easily removed by pulling the removing handle 14.