A method for manufacturing electrodes for a spark plug that reduces manufacturing time. The method includes a supply step of supplying a workpiece to a die for extrusion forming, wherein the die has a supply hole and an extrusion hole located adjacent to the supply hole for forming the workpiece to have a predetermined cross-sectional shape. The supply hole has a cross section greater than a cross section of the extrusion hole. The method also includes a forming step of pushing the workpiece, supplied to the supply hole, through the extrusion hole so as to form the workpiece into a shape corresponding to the cross section of the extrusion hole. In the supply step, the workpiece is supplied such that a plurality of workpieces form a vertical line in the die.