PURPOSE: To obtain the title ferrite whose production has been considered impos sible by the conventional dry process by pulverizing a powder mixture consisting of pulverous Fe2O3 and divalent metal oxide in a specified compositional ratio, mixing the pulverized product, compression molding the mixture, calcining in the air, and calcining further in vacuum.

CONSTITUTION: A ferrite of a divalent metal (Mi) is prepd. from the above described compression molded product consisting of an oxide of Mi and Fe2O3 (hematite) in accordance with the following reaction formula: MiO+Fe2 O3→MiFe2O4 (I). Succeedingly, Fe3O4 (magnetite) is prep. from residual Fe2O3 at high temp. in vacuum in accordance with the reaction formula (II): Fe2O3→Fe3 O4+1/202 (II). Aimed ferrite contg. Fe2+ ions is obtnd. thereafter by allowing MiFe2O4 obtd. by formula (I) to react with Fe3O4 obtd. by formula (II) in accor dance with the reaction formula: xFe3O4+(1-x)MiFe2O4→(FexMi1-x)Fe2O4 (III). Suitable MiO is, for example, NiO. A ferrite contg. divalent Fe ions and having an optional shape and high purity is obtd. in a short time by the method of this invention.