The　microstructures　of　B-bearing　cast　steel　containing　0.8-1.2　wt.%B,　0.8-1.2　wt.%Cr,　1.0-1.5　wt.%Mn,　0.6-1.0　wt.%Si　and　0.10-0.25　wt.%C　have　been　characterized　by　means　of　optical　OM,　SEM,　EPMA　and　XRD.　The　solidification　structure　of　B-steel　consists　of　pearlite,　ferrite,　martensite　and　boride　(Fe2B),　while　the　hardness　is　1430-1480　HV.　Borides　distribute　along　the　grain　boundary　in　the　form　of　eutectic.　Fine　lath　martensite　and　eutectic　Fe2B　can　be　obtained　by　water　quenching　at　1223　K-1273　K.　The　hardness　and　impact　toughness　of　the　B-steel　exceed　55　HRC　and　150　kJ/m(2),　respectively.　The　abrasion　resistance　determined　using　a　pin　abrasion　tester　is　obviously　higher　than　that　of　the　martensitic　cast　steel　and　nears　to　the　high　chromium　white　cast　iron.