Forming mechanism and the surface properties of the micro nanostructured coating are introduced briefly in the article, and the main factors leading to the improvement of hardness and wear resistance of the cladding coating are analyzed , namely the join of nanometer crystal hard phase. It focuses on the causation of nanocrystalline organization existed in the micro nanostructured coating, that is the surface layer of the metal are ultra high speed quenched because of the shock chilling and shock heating in the cladding process. At the same time, the problem currently existed in electro-spark micro nano technology is discussed and future research interests are correspondingly proposed.