This paper deals with machinability of BN added steels in face milling. In this study, work materials including different content levels of Al, B and N were cut with a carbide tool P10, a TiN cennet tool, a TiC cermet tool and a TiCN coated carbide tool. When face milling the steels with the carbide tool P10 and the cermet tools at the cutting speed over 200 m/min, steels containing Al, B and N caused much smaller flank wear but larger crater wear than S45C. While in face milling of BN added steels by the TiCN coated tool at the cutting speed of 300 m/min, the crater wear rate was drastically reduced than that of S45C. In the cace of face milling in low oxygen atmosphere, crater wear of the carbide tool were also reduced. It was concluded that the machinability of BN added steels in face milling was influenced by tool materials, Al, B and N content of work materials and cutting atmosphere.