In this Communication, we report a high efficiency electrocatalyst for electrochemical water oxidation based on an Fe-doped Ni2P nanosheet array on a conductive carbon cloth. This catalyst shows a low onset overpotential of 190 mV, and it demands overpotentials of only 215 and 235 mV to drive 50 and 100 mA cm(-2), respectively, with high electrochemical durability. This work offers us an attractive earth-abundant 3D catalyst electrode in water-splitting devices toward the mass production of hydrogen fuels for applications.