Abstract: Utilization of CO₂ into value-added products is one of the important ways to achieve carbon neutrality. Metal-organic frameworks (MOF) have been proven to be promising and effective materials, relying on the characteristic of porosity, functional adjustability, abundant active sites and high specific surface area. Single-atom catalysts (SAC) have emerged as a new frontier due to well-defined structures and maximum atom utilization efficiency (100%). By combining the merits of both, MOF-based SAC exhibits enormous potential in photocatalytic/electrocatalytic CO₂ reduction reactions. The review systematically summarized the latest research progress of MOF-based SAC in photocatalytic/electrocatalytic CO₂ reduction. The diverse fabrication strategies and principles of MOF-based SAC, including MOF-immobilized SAC and MOF-derived SAC, as well as unique advantages demonstrated in photocatalytic/electrocatalytic CO₂ reduction, were discussed. Finally, a perspective on MOF-photocatalysts/electrocatalysts for CO₂ reduction was given.