PURPOSE: To produce a magnetic material having low magnetic core loss and high magnetic flux density by depositing Co on the surface of a thin band plate of a specified thickness consisting of pure Fe and performing recrystallization under a specified conditions.

CONSTITUTION: Co is deposited on the surface of a thin band plate of 10 to 1000μm thickness consisting of pure iron which does not contain any other component except inevitable impurities, in an amount to provide a ≤5wt.% Co content of the thin band plate and then the recrystallization is performed at ≤γ/α transformation point (910°C). By the recrystallization, the Co concn. of the surface and the center of the thin band plate are adjusted to 5 to 80wt.% and to <5wt.% respectively, and more than a half of the total crystal grains that constitute the thin band plate have their (100) plane in parallel with the face of the thin band plate. Thus the magnetic material having high magnetic flux density and low magnetic core loss can be produced.