High-pressure water jet cutting is cutting by high-speed jet with high kinetic energy (sometimes called high-speed water jet machining), which belongs to the category of high-energy beam machining like laser, ion beam and electron beam. As a high-tech, high-pressure water jet cutting is a revolution in the cutting field in a sense, which has a very broad application prospect. With the maturity of technology and the overcoming of some limitations, it is a perfect complement to other cutting technologies. At present, its uses and advantages are mainly reflected in difficult-to-machine materials, such as ceramics, cemented carbide, high-speed steel, die steel, quenched steel, white cast iron, tungsten-molybdenum-cobalt alloy, heat-resistant alloy, titanium alloy, corrosion-resistant alloy, composite materials (FRM, FRP, etc.)), calcined ceramics, high-speed steel (below HRC30), stainless steel, high-manganese steel, die steel and martensite steel (HRC & In the United States, almost all automobile and aircraft manufacturers have applications. It has been successfully used in the following industries: automobile manufacturing and repair, aerospace, machining, national defense, military industry, weapons, electronic power, petroleum, mining, light industry, building materials, nuclear industry, chemical industry, shipbuilding, food, medical treatment, forestry, agriculture, municipal engineering and so on.