Seawater electrolysis technology for hydrogen production has attracted worldwide attention due to the abundant seawater resources. Herein, we proposed core-shell Ru@MnO2 nanowires (NWs) with α/β-MnO2 NWs as the core and amorphous Ru as the shell, in which the Ru@α-MnO2 NWs exhibited lower overpotential and better stability. More importantly, they can operate stably as a bifunctional catalyst for more than 250 h and maintain excellent catalytic performance when driven by solar energy.