Abstract: High-performance coatings on diamond/Cu composite materials were obtained by nickel plating. Three different coatings prepared by two different electroless plating processes and one electroplating process were investigated and compared after welding heat treatment using a vacuum furnace. The adhesion and corrosion resistance of the coatings after welding heat treatment were tested. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to observe the surface appearance of the coatings and the phase structure before and after welding heat treatment, respectively. It is shown that after welding heat treatment, for the electroless plating coatings using sodium citrate as a complexing agent, the high temperature resistance, bonding strength and corrosion resistance are better than those of the electroplating or electroless plating coatings using butanedioic acid as a complexing agent.