Abstract: In order to study the composite electrodeposition process of diamond consolidated abrasive grinding discs, the preparation technology and properties of Ni-diamond composite coating are studied in this paper.The influences of diamond concentration, current density, temperature and deposition time on the quality of composite coating are studied by scanning electron microscopy, microhardness tester and friction and wear tester.A series of preferred Ni-diamond composite electrodeposition process parameters are obtained:diamond concentration 40g/L, current density 3A/dm², temperature 50℃, deposition time 90 min.The surface of Ni-diamond composite coating is flat, the diamond powder has a uniform deposition, and the wear resistance of the composite coating is obviously improved compared with the traditional nickel layer.