Herein, a universal approach is proposed to prepare a nitrogen-doped mesoporous Ru film with uniform pore size on nickel foam (N-mRu/NF) as an active bifunctional catalyst for energy-saving hydrogen production. The N-mRu/NF requires an ultrasmall overpotential of -60 and 62 mV to achieve 100 mA cm-2 for the hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR), respectively. When used for HER-HzOR electrolysis, N-mRu/NF requires low voltages of 0.023 and 0.184 V at 10 and 100 mA cm-2, respectively.