The rare earth permanent magnet

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The invention provides an R-T-B based sintered magnet capable of maintaining a high coercive force as compared with the prior art. The invention provides a rare earth based permanent magnet, characterized in that the rare earth based permanent magnet is formed by a sintered compact with an R-T-B based composition, wherein, R contains R1 and R2 as the necessity, R1 represents at least one rare earth element including Y and excluding Dy, Tb and Ho, and R2 represents at least one from the group made of Dy, Tb and Ho; the main phase grains have a core-shell structure in which a core part and shell part coating the core part are contained; when the atom concentrations of R1 and R2 in the core part and the atom concentrations of R1 and R2 in the shell part are defined as R1, R2, R1 and R2, respectively, R1 R1, R2 > R2, R1 R2 and R2 R1; and relative to all the main phase grains observed at the cross-section of the sintered compact, the ratio occupied by the main phase grain having the core-shell structure is 5% or more.