Provided is a spot welding electrode housing apparatus having a reduced size such that an operation of mounting electrodes on a welding gun is less likely to affect a line takt time. Specifically, a rotation regulator 7 positioned adjacent to a rotating plate 2 in a direction of a rotation axis is configured to allow the rotating plate 2 to abut against an electrode 10 housed and held in a first recess 23 or a second recess 24 and thereby to regulate a rotation of the rotating plate 2 toward one direction around the rotation axis when the rotating plate 2 rotationally biased by a spiral spring 6 toward the one direction around the rotation axis is allowed to rotate toward the other direction around the rotation axis against a biasing force of the spiral spring 6.