The invention belongs to a method and a device for mechanical grinding, namely a process and equipment for grinding nanometer fluid. The nanometer fluid grinding process comprises that nanometer-grade solid containing powder is supplied to a grinding area as a cooling lubrication medium in a grinding process. The equipment is characterized in that: the equipment comprises a lubricant storage tank, a water storage tank, a nanometer-grade powder storage tank and a high pressure air pump, which are arranged on a machine frame; and various mediums are mixed with the high pressure air, the mixtureenters an atomizing chamber for mixing atomization and is conveyed to the grinding processing area by a hose and a spray head. Because the coefficient of thermal conductivity of the nanometer powder is high, the nanometer fluid can bring away a large amount of grinding heat when passing the high-temperature area, so that the cooling property of the grinding medium is enhanced, and the defect of the poor cooling effect of the micro lubrication is overcome; and simultaneously, because the weight of the nanometer powder is light, the characteristics and the advantages of the micro lubrication are maintained, the active effects of high processing quality, low cost and no pollution are achieved, and the method becomes the fourth generation lubrication cooling grinding process after wet processing, dry processing and micro lubrication.