To provide magnetic abrasive grains free from contamination by magnetic substance, imparting a highly effective precision grinding.

The invention relates to the magnetic abrasive grains comprising resin particles coated by the abrasive particles wherein the resin particles comprise a resin dispersing magnetic substance, or resin particles obtained by coating the magnetic substance with the resin and the volume average particle diameter of the abrasive particles is 1/10 of the volume average particle diameter of the magnetic substance. The method for producing the magnetic abrasive grains comprises a dispersing process heating a thermoplastic resin composition comprising at least a thermoplastic resin and the magnetic substance and a solvent without compatibility to the composition to a temperature higher than the melting point of the composition, and mixing to disperse into fine particles, a process cooling the product fine particles of the thermoplastic resin composition to a temperature below the melting point of the thermoplastic resin composition to obtain spherical resin particles having 1-500 μm of volume average particle diameter dispersing the magnetic substance, and a process coating the resin particles containing dispersed magnetic substance with the abrasive grain.

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