A　FeCrNiCoMnBx　high-entropy　alloy　coating　was　prepared　by　laser　cladding　on　a　low　carbon　steel　substrate.　The　effect　of　boron　addition　on　the　microstructure,　hardness,　and　wear　resistance　of　FeCrNiCoMnBx　was　studied.　The　formation　mechanism　of　stacking　faults　(SFs)　in　boride　was　analyzed.　Results　show　that　the　coating　has　a　simple　fcc　structure　with　boride　precipitation.　Boride　precipitation　is　mainly　the　(Cr,Fe)(2)B　phase　when　the　boron　content　x　is　increased　from　0.25　to　0.75.　However,　as　the　value　of　x　reaches　1.0,　many　(Fe,　Cr)(2)B　phases　are　found　in　the　boride.　The　volume　fraction　of　borides　increases　with　the　increase　in　boron　content.　Hardness　and　wear　resistance　of　the　coating　are　also　enhanced.　(Fe,Cr)(2)B　borides　have　high-density　SFs　on　the　((1)　over　bar　10)　planes.　The　generation　of　SFs　in　(Fe,Cr)(2)B　is　probably　attributed　to　the　(Fe,　Cr)(2)B　-＞(Cr,Fe)(2)B　phase　transformation　by　a　simple　shear　of　(Fe,Cr)(2)B　((1)　over　bar　10)　planes　(with　shear　vectors　at　nearly　1/4　[11　(1)　over　bar).