Electrocatalytic CO2 reduction via renewable electricity provides a sustainable way to produce valued chemicals, while it suffers from low activity and selectivity. Herein, we constructed a novel catalyst with unique Ti3C2Tx MXene‐regulated Ag−ZnO interfaces, undercoordinated surface sites, as well as mesoporous nanostructures. The designed Ag−ZnO/Ti3C2Tx catalyst achieves an outstanding CO2 conversion performance of a nearly 100% CO Faraday efficiency with high partial current density of 22.59 mA cm−2 at −0.87 V versus reversible hydrogen electrode. The electronic donation of Ag and up‐shifted d‐band center relative to Fermi level within MXene‐regulated Ag−ZnO interfaces contributes the high selectivity of CO. The CO2 conversion is highly correlated with the dominated linear‐bonded CO intermediate confirmed by in situ infrared spectroscopy. This work enlightens the rational design of unique metal‐oxide interfaces with the regulation of MXene for high‐performance electrocatalysis beyond CO2 reduction.