Oxidative steam reforming of methanol is an attractive route for auto-thermal methanol conversion with hydrogen production, but requires oxygen as feedstock for guaranteeing relatively high hydrogen quality. Here, a new pathway, lattice oxygen-induced oxidative steam reforming of methanol, is proposed, which enables low-temperature methanol activation and inherent air separation in a redox looping manner. Specifically, ASPEN Plus software was adopted to verify the feasibility of auto-thermal conversion of methanol via Cu↔Cu2O looping and provided a comprehensive understanding of the associated process via operating parameter optimization. Meanwhile, a series of CuOx/Ca2Fe2O5 (0≤x≤1) catalytic oxygen carriers (COCs) are prepared, which goes through the reduction → catalytic methanol conversion →re-oxidation. Results indicate that 40% Cu-loaded CuOx-Ca2Fe2O5 shows the highest catalytic activity of the synthesized COCs, and the presence of Ca2Fe2O5 tunes the redox activity and mobility of the lattice oxygen, obtaining a H2 production rate of 37.6 μmol·H2∙g−1·COC·s−1 at 240°C. The evolution pathway of methanol is investigated using CH3OH-pulse and in situ DRIFTS, which follows the sequence: CH3OH full oxidation →formaldehyde intermediate → methyl-formate intermediate as the amount of lattice oxygen decreases. This study applies the concept of chemical looping into auto-thermal conversion of methanol, which provide new implications for the development of low-temperature hydrogen production from methanol.