An ultrafine amorphous Ni-Co-B alloy powder, prepared by chemical reduction, showed much higher catalytic activity than Raney nickel in the hydrogenation of benzene. The only product was cyclohexane. Its amorphous structure was verified by DSC, XRD and EXAFS. TEM was used to determine its morphology. The particle size was found to be about 10 nm. The chemical composition of the sample was Ni32.5Co31.7B35.8 as determined by ICP. XPS showed that the surface of the sample was nickel-rich.