PURPOSE: To obtain manufacturing method of a magnet roll with high magnetic force and productivity by a method wherein a shaft and resinous magnet are molded in the state of one body and make them orientate by magnetic field.

CONSTITUTION: Ferrite powder and macromolecule material are kneaded and composite resinous magnet member is obtained crushing after cooling. A roll state magnet roll, which consists of magnet member 9 with a shaft 8 at central part, is molded out of the above-stated member using an injection molding device. Subsquently, the magnetic member 9 is heated in thermostatic tank up to be plastic state, and is inserted immediately into an oriantation mold 12 made by magnetic metallic member 10 and nonmagnetic metallic member 11, pressing in an axis of a shaft direction with a pressing device constituted by pressure jig 13 and an air cylinder 14, and is subjected to contact with inner wall face of the metallic mold. At the same time as accomplishment of molding, a coil 15 is conducted and the magnet roll molded with one body, which has the shaft 8 at central section, is obtained by means that an axis of easy magnetization of ferrite particle in the generated magnetic field is orientated in a direction of magnetic lines of force.