Formate dehydrogenases (FDH) catalyze reversibly the interconversion of CO 2 to formate. They belong to the family of molybdenum and tungsten-dependent oxidoreductase. For several decades, scientists have been synthesizing structural and functional model complexes inspired by these enzymes. These studies not only allow for finding certain efficient catalysts, but also in some cases to better understand the functioning of the enzymes. However, FDH models for catalytic CO 2 reduction are less studied compared to the oxygen atom transfer (OAT) reaction. Herein, we present recent results of structural and functional models of FDH.