Abstract: The coating ways of amorphous Fe₇₈Si₉B₁₃ alloys and its influence to magnetic properties are studied.It is found that coating thickness is even and the coated Fe₇₈Si₉B₁₃ alloys performs good property of voltage withstand through the suitable coating way;For the non-coating amorphous Fe₇₈Si₉B₁₃ alloys and the coatings,it is showed that they have the same diffraction pattern after longitudinal field annealing;For the coated amorphous Fe₇₈Si₉B₁₃ alloys,although it has a little effect on its static magnetic properties,it reduces the core loss effectively in the working conditions of high frequency.It is useful for the amorphous devices which are used in high frequency.