Through comprehensive compatibility optimization,a environmentally friendly high performance semisynthetic cutting fluid was developed by selected the excellent performance of base oil,lubricant,antirust anticorrosion agent,emulsifier,hard water stabilizer additive etc,which does not contain toxic and harmful substances such as mineral oil,sulfur,phosphorus,chlorine,boron,phenol,formaldehyde,secondary amines,heavy metals,sodium nitrite etc.The performance tests show that the developed semisynthetic cutting fluid has excellent physical and chemical properties,stability,lubrication and antirust corrosion resistance.The practical application show that the developed semisynthetic cutting fluid can be used for the processing of difficult materials such as high alloy steel,nickel alloy,titanium alloy and all kinds of aluminum alloys,which can meet the requirements of milling,boring,drilling,tapping,broaching,tapping screw and other processesIt can extend the tool life and improve the processing efficiency,and it has a very good application prospect.