The　aim　of　the　present　study　is　to　investigate　the　effects　of　austenitizing　temperature　on　the　microstructures,　hardness　and　impact　toughness　of　austenitic　stainless　steel　containing　1.5-2.5　wt.%　B.　It　is　observed　that　the　phases　present　in　the　heat　treated　B-bearing　stainless　steel　are　austenite　and　M-2(B,C)　borocarbide　and　the　M2(13,C)　borocarbide　has　no　obvious　change　when　the　austenitizing　temperature　is　lower　than　950　degrees　C.　When　the　austenitizing　temperature　exceeds　950　degrees　C,　parts　of　the　borocarbide　networks　are　broken,　and　some　isolated　borocarbides　appear.　Moreover,　there　is　no　significant　change　in　the　borocarbide　volume　fraction　unless　the　austenitizing　temperature　is　beyond　1050　degrees　C.　As　the　austenitizing　temperature　exceeds　1050　degrees　C,　the　borocarbide　volume　fraction　decreases.　The　microhardness　of　metallic　matrix　and　Vickers　hardness　of　B-bearing　stainless　steel　increase　with　the　increase　of　austenitizing　temperature,　and　the　microhardness　of　borocarbides　has　no　obvious　change　at　different　austenitizing　temperature.　The　change　of　austenitizing　temperature　has　no　obvious　effect　on　the　impact　toughness　of　B-bearing　stainless　steel　also.　(C)　2008　Elsevier　Ltd.　All　rights　reserved.