PURPOSE: A spot welding gun is provided to prevent the interference with a flange part of a welded object by simply adjusting the height of a lower electrode with an adjusting bolt. CONSTITUTION: A spot welding gun comprises upper and lower electrodes(107) arranged in a gun body(103); and a driving cylinder. The driving cylinder drives the upper electrode. The height of the lower electrode is adjusted by a height adjusting unit arranged in one side of the gun body.
