The optimizing utilization of carbon resources has drawn wide attention all over the world, while exploiting the high-efficiency catalytic routes remains a challenge. Here, a direct methanol synthesis route is realized from pure CO and H2O over 10%Cu/t-ZrO2 catalyst, where the time yield of methanol is 144.43 mmol molCu−1 h−1 and the methanol selectivity in hydrocarbons is 100%. The Cu species highly dispersed in the t-ZrO2 support lead parts of them in the cationic state. The Cu+ sites contribute to the dissociation of H2O, providing the H* source for methanol synthesis, while the formed Cu0 sites promote the absorption and transfer of H* during the reaction. Moreover, the H2O is even a better H resource than H2 due to its better dissociation effectivity in this catalytic system. The present work offers a new approach for methanol synthesis from CO and new insight into the process of supplying H donor.