Abstract: Copper nanowires (CuNWs) are promising electrode materials, especially for used in flexible and transparent electrodes, due to their advantages of earth-abundant, low-cost, high conductivity and flexibility. However, the poor stability of CuNWs against oxidation and chemical corrosion seriously hinders their practical applications. Herein, we propose a facile strategy to improve the chemical stability of CuNWs by in situ coating of carbon protective layer on top of them through hydrothermal carbonization method. The influential factors on the growth of carbon film including the concentration of the glucose precursor (carbon source), hydrothermal temperature, and hydrothermal time are systematically studied. By tailoring these factors, carbon layers with thickness of 3–8 nm can be uniformly grown on CuNWs with appropriate glucose concentration around 80 mg·mL⁻¹, hydrothermal temperature of 160–170°C, and hydrothermal time of 1–3 h. The as-prepared carbon-coated CuNWs show excellent resistance against corrosion and oxidation, and are of great potential to use broadly in various optoelectronic devices.