The diamond saw blade s a kind of composite material, which is made up of diamond particles and metal powder by sintering. Because diamond belongs to nonmetal, so there is high interface energy between diamond and metal(or alloy),which makes it difficult for metal or alloy to infiltrate the diamond .The diamond is easy to fall off from the saw blade in the course of cutting, so the diamond can"t be made full use, which will reduce diamond"s life. This subject tries to resolve this difficult problem by using of the diamond coated with metal.The electroless plating solution is made after a lot of thermodynamics and kinetics analysis, amending the composition of saw blade and technics time after time. Three kinds of diamond are got finally , which are Ni-coated diamond, Ti-coated diamond and Ti-Ni coated diamond. The diamond surface is all covered by metal. The morphology of diamond and the interface between plating layer and diamond are examined by SEM. The phase constitutions are measured by means of X-ray diffraction. We find that the bonding between the diamond and Ni-layer is mechanism, but the bonding between the diamond and Ti-layer is chemical bonding. There is a gap between the diamond and Ni-layer. There is compact combination and compounds, such as TiC, TiNi formed at the interface between the diamond and Ti-layer.Three kinds of diamond coated with metal are applied to the saw blades. We observe the sawteeth"s wear morphology, diamond"s pull-out ratio and matrix"s control to diamond. The results show that the performance is high than the uncoated diamond saw blade. The saw blade of Ti-Ni coated diamond is the best among them, and the consumers have praised it highly. This research has provided a reference to improve the saw blade"s performance.