Machining is important in almost all manufacturing processes. However, drawbacks of poor machinability are becoming prevalent in industry. The main problems associated with machining of metal materials are mostly related to tool wear and surface quality. Contributed by the heat generated at the tool/workpiece sliding surfaces, many machining techniques have been developed to control the amount of heat generated, such as application of cutting fluid. Recent trends of environmental-friendly machining by using cryogenic cutting fluid are becoming popular. The cryogenic machining employed several types of cryogen such as liquid nitrogen (LN), oxygen, helium (LHe), methane, ethane, and argon to reduce the cutting temperature.  The application of Liquid Nitrogen (LN) as cryogenic cutting fluid in turning AISI 4340 alloy steel has shown improvement in reducing the cutting temperature by 35% – 55%. This could lead to a reduction in tool wear and reduce the machined surface alteration.