To provide an electrifying heating device for a shaft-shaped workpiece by which a uniform electrifying heating state can be easily acquired on the surface of the shaft-shaped workpiece by mutually differentiating a contact form of a right and left pair of contact electrodes to the surface of the shaft-shaped workpiece, and highly-accurate hardening quality can be obtained on the heating surface.

The electrifying heating device for a shaft-shaped workpiece is equipped with the right and left pair of electrifying electrodes disposed in an opposed manner at predetermined intervals along a longitudinal direction of the shaft-shaped workpiece with which predetermined surfaces of the shaft-shaped workpiece come into contact respectively, and a power supply device that supplies a current of a predetermined frequency to the pair of the electrifying electrodes and electrically heats the predetermined surfaces of the shaft-shaped workpiece. The pair of electrifying electrodes are configured so as to come into contact with two positions in the longitudinal direction of a heating surface of the shaft-shaped workpiece in mutually different forms according to the presence and absence of a slit of the contact surface, the size of the slit width, etc.