A rare earth permanent magnet having excellent corrosion resistance and method of manufacturing the

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This invention provides a highly corrosion-resistant rare earth permanent magnet. The rare earth permanent magnet comprises an R-T-B-base or R-T-B-M-base permanent magnet produced by hot compaction of an R-T-B-base or R-T-B-M-base magnet powder subjected to dehydrogenation/recombination treatment by a method comprising heating the R-T-B-base or R-T-B-M-base magnet powder in a hydrogen atmosphere to conduct hydrogenation/phase decomposition and then conducting vacuum drawing in the heated state, and a protective film of a composite oxide (R, Fe)2O3, composed mainly of R and Fe, formed on the surface of the permanent magnet, wherein R represents a Y-containing rare earth element; T represents Fe or a component obtained by replacing a part of Fe with Co; M represents one or at least two of Si, Ga, Zr, Nb, Mo, Hf, Ta, W, Al, Ti, and V; and B represents a boron element.