Producing low–cost non–precious metal catalysts in large scales to be used as air–cathodes for efficient oxygen reduction and evolution reactions in Li–O2 batteries is a demanding task. Herein, we report a simple technique for the synthesis of a carbide composite comprising molybdenum and tungsten with a robust nanowire structure. When applied as an air–cathode electrocatalyst in Li–O2 batteries, the nanowire composite delivered high specific discharge capacity with reversibility and cyclability. This work provides a novel approach for tailoring nano–architectures and thereby achieving high–power Li–air batteries.