The development of the hydrogen electrode is vital for the application of alkaline polymer electrolyte fuel cells (APEFCs). In this study, a series of Ni(OH) 2 decorated Ni/C catalysts (Ni(OH) 2 -Ni/C) were prepared by a three-step electrochemical treatment of Ni/C. The existence of Ni(OH) 2 was demonstrated by X-ray photoelectron spectroscopy (XPS), and the surface molar ratio of Ni(OH) 2 /Ni of the samples was estimated via an electrochemical method. The HOR catalytic activity of the catalysts was evaluated by a rotation disk electrode (RDE) method, and a "volcano plot" was established between the HOR exchange current ( j 0 ) and the surface molar ratio of Ni(OH) 2 /Ni. On top of the "volcano", the surface molar ratio of Ni(OH) 2 /Ni is 1.1:1, the j 0 of which was 6.8 times of that of Ni/C. The stability of the samples toward HOR was evaluated to be good. Our study added a systematic experimental evidence to the HOR research, showing that the HOR catalytic activity of Ni can be deliberately controlled via decoration of Ni(OH) 2 , which may help understanding the HOR mechanism on Ni.