To provide a heating roller in an induction heating roller device which is structured so as to have as uniform temperature distribution as possible for the heating roller, an induction heating roller device using it, a fixed device and an image forming device.

The heating roller TR in the induction heating roller device is provided with a hollow roller base body BB made of a non-conductive material, and secondary coils ws with more than one turn wound round in a circumferential direction of the roller base body BB to form a closed circuit. An induction coil device IC, inserted inside the heating roller TR, is provided with a bobbin, CB, primary coils wp, and a wiring pair WP. The primary coils wp and the secondary coils ws, preferably form an air-core transformer coupling.