PURPOSE: To realize a high permeability and a low magnetic loss even in a high-frequency region by a method wherein a highly crystalline ferrite magnetic powder whose spinel-property has been advanced sufficiently is pressurized and molded and, after that, it is heat-treated at a baking temperature or lower and sintered.

CONSTITUTION: As various electronic apparatuses are designed for high frequencies, it is requested to improve the magnetic loss of a ferrite magnetic substance in a high frequency region at MHz or higher. At the manufacturing method of the ferrite magnetic substance, a highly crystalline ferrite magnetic powder whose spinel-property has been advanced sufficiently by a high-temperature baking operation is pressurized and molded and, after that, it is heat-treated at a baking temperature or lower for a ferrite magnetic powder and sintered. In this manner, the ferrite magnetic powder itself which is used is sintered at a high temperature and is already advanced to be nearly completely crystalline. As a result, when it is heat-treated, crystal particles are hardly grown and a magnetic substance containing uniform crystal particles whose particle size is fine can be obtained as a final product. Thereby, it is possible to obtain the ferrite magnetic substance whose perameablity is high and whose magnetic loss is low even in a high-frequency region.