Comprehensive SummaryElectrocatalytic reduction of CO2 to valuable products possesses huge potential to alleviate environmental and energy crisis. It is well known that Ag favors the conversion of CO2 to CO but the exposed active sites and stability are still rather limited. In this study, a novel one‐dimensional Ag‐based metal‐organic framework (1D Ag‐NIM‐MOF) was successfully synthesized and used in the electrocatalytic CO2 reduction reaction (CO2RR) for the first time. As a result, the Faradaic efficiency of CO achieved 94.5% with current density of 12.5 mA·cm–2 in an H‐type cell and 98.2% with current density of 161 mA·cm–2 in a flow cell at –1.0 V (vs. RHE), which stands as a new benchmark of Ag‐based MOFs in the electrocatalytic CO2RR. The excellent performance of 1D Ag‐NIM‐MOF is attributed to its peculiar one‐dimensional structure, which is beneficial for diffusion of reactants and products, and exposure of much more catalytic sites. Compared to commercial Ag nanoparticles, 1D Ag‐NIM‐MOF exhibits superior electrocatalytic CO2RR performance with higher catalytic activity and stability.