Polycrystalline diamond powder (um) is synthesized by high-performance explosives undernegative oxygen conditions. Under the conditions of ultra-high pressure and high temperaturewhich are necessary for synthesizing diamond at the moment of detonation, the free carbonatoms generated by the explosive form a micron-scale. Diamond particles, multi-diamond finepowder is different from single crystal diamond powder synthesized under static pressure whichhas better self-sharpening.