The　microstructure　and　magnetic　properties　were　studied　for　the　sintered　Nd-Fe-B　permanent　magnet　doped　with　terbium　(Tb)　nanoparticles.　Investigation　shows　that　Tb　is　enriched　as　Tb2Fe14B　and/or　(Nd,Tb)(2)Fe14B　phase　in　the　surface　region　of　the　Nd2Fe14B　matrix　grains　indicated　by　the　remarkable　enhancement　in　the　magnetocrystalline　anisotropy　field　of　the　magnet.　Furthermore,　the　Tb-rich　grain　surface　region　with　high　crystal　anisotropy　increases　the　nucleation　field　of　reverse　domains　in　the　demagnetization　process.　As　a　result,　the　magnet　doped　with　a　small　amount　of　Tb　nanoparticles　possesses　enhanced　coercivity　without　sacrificing　its　magnetization.