The tribological properties of Fe–Cr–B alloys were studied sliding against SiC ball in liquid paraffin oil. The boron played an important role in improving tribological properties of alloys. The friction coefficients of alloys decreased with the increase of normal load and sliding speed. The Fe–Cr–B alloys showed better wear resistance than that of Fe–Cr alloy. Fe-21 wt.% Cr-7 wt.% B alloy had the best tribological properties. The wear mechanism of Fe–Cr alloy was abrasive wear and plastic deformation. The wear mechanism of Fe–Cr–B alloys was microploughing and fatigue flaking pits.