The R-T-B-based rare earth magnet 100 of the present disclosure includes a main phase 10 having an R2T14B-type crystal structure and a grain boundary phase 20. The average grain size of the main phase 10 is from 1.0 to 10,0 μm. The main phase 10 has a core portion 12 and a shell portion 14. The total content ratio of cerium, lanthanum, yttrium and scandium is higher in the core portion 12 than in the shell portion 14. The total content ratio of neodymium, praseodymium, gadolinium, terbium, dysprosium and holmium is higher in the shell portion 14 than in the core portion 12. The R-T-B-based rare earth magnet 100 contains from 0.05 to 0.50 at % of carbon. The content ratio of the carbon is higher in the grain boundary phase 20 than in the main phase 10.