Ni/(Ni + RuO2) active cathodes were prepared by simultaneous electrodeposition of Ni and RuO2 on a Ni substrate from an electrolyte solution (Watts bath) in which RuO2 particles were suspended by vigorous stirring. The resulting cathodes were electrochemically characterized and it was found that the enhanced electrocatalytic activity of the cathodes was mainly ascribable to the increase of active sites or the content of RuO2 particles. Furthermore, the performance of the Ni/(Ni + RuO2) active cathodes was evaluated for the use in chlor-alkali electrolysis in a laboratory scale. The hydrogen overvoltage of the cathodes was confirmed to be very low and the high durability was observed under the industrial chlor-alkali electrolysis conditions. In addition, the cathodes had excellent tolerance to repeated short-circuiting.