Abstract: The dry turning of hardened steel was carried out by ceramic tool (CC6050), CBN tool (CB7025) and carbide tool (GC2025) to study the wear curves and wear morphology of the tools after turning, and the abrasion mechanism of the tools was analyzed. The results show that the CB7025 tool had the longest working life, followed by the CC6050 tool, and the GC2025 tool had the shortest working life. The wear patterns on the rake face of the CC6050 and CB7025 tools were both crater wear; there were clearly wear lands on the flank of these tools. The dominant wear mechanisms of tools included diffusion wear, oxidation wear and abrasive wear, but the adhesive wear was not easy to happen because the chemical affinity between Al, Si elements contained in the CC6050 tool and workpiece material was small; the phase change wear was found in CB7025 tool, the adhesive wear was also found in GC2025 tool.