MnxBi100-x　(x=48,　50,　55　and　60)　alloys　were　prepared　by　the　induction　melting　technique,　and　subjected　to　melt　spinning　and　subsequent　ball　milling.　XRD　shows　that　the　as-milled　powders　were　mainly　composed　of　LTP　MnBi.　Increasing　melt　spinning　speed　and　reducing　annealing　treatment　time　can　restrain　the　segregation　of　Mn　from　MnBi　liquid　during　the　peritectic　reaction,　which　increases　the　LTP　MnBi　content.　High　energy　ball　milling　results　in　the　coercivity　increase　of　MnBi　powders.　With　increasing　milling　time,　the　coercivity　increases　initially　and　then　decreases　gradually.　After　ball　milling　for　4　h,　the　coercivity　of　the　MnxBi100-x　powders　is　11.4　kOe　for　x=48　and　14.8　kOe　for　x=55.　The　optimal　composition　of　Mn48Bi52　with　more　LTP　has　an　M-2.2　(T)　of　49.98　emu/g　and　an　M-r　of　33.57　emu/g.　(C)　2012　Elsevier　B.V.　All　rights　reserved.