The silicon-coated iron powder was evenly mixed with corundum powder and high temperature binder. After tabletting and sintering, followed by crushing and screening, the magnetic abrasive with a certain size was obtained. Scanning electron microscope (SEM), Energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) were respectively used to characterize the morphology, elemental composition and the crystalloid structures of magnetic abrasive. The ferromagnetic phase and abrasive phase were combined firmly. The magnetic abrasive prepared showed a good grinding ability, whose durable time was up to 24 min. Irregular particles was obtained by smashing the magnetic abrasive, mainly composed of Al2O3, Fe2O3, α-Fe, AlFeO3, (Al, Fe)7BO3(SiO4)3O3.