B-lean　Ga-doped　sintered　NdFeB　magnets　can　reduce　the　use　of　heavy　rare　earth　based　on　high　coercivity，so　they　have　significant　research　value.　In　this　paper，high-performance　48H　B-lean　Ga-doped　sintered　NdFeB　magnets　containing　0.2%　Ti　and　Nb　were　prepared，respectively.　The　effects　of　Ti　and　Nb　element　substitution　on　magnetic　properties，microstructure，element　distribution，and　abrasion　resistance　of　both　magnets　were　analyzed.　Compared　with　Ti　substituted　magnets，Nb　substituted　magnets　have　more　continuous　and　thicker　grain　boundary.　Therefore，a　better　magnetic　isolation　effect　is　obtained　and　the　magnet　has　a　higher　coercivity.　In　addition，Nb　substituted　magnets　have　relatively　poor　fracture　resistance，areeasy　to　wear，therefore　exhibit　better　machinability　because　Nb　is　more　likely　to　be　enriched　at　the　triangular　grain　boundaries.　This　provides　meaningful　guidance　for　optimizing　the　microstructure　to　prepare　high-performance　B-lean　Ga-doped　sintered　magnets.　©　2023　Chinese　Society　of　Rare　Earths.　All　rights　reserved.