In enzymology, a formyltetrahydrofolate deformylase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are 10-formyltetrahydrofolate and H<sub>2</sub>O, whereas its two products are formate and tetrahydrofolate.
This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amides. The systematic name of this enzyme class is 10-formyltetrahydrofolate amidohydrolase. This enzyme participates in glyoxylate and dicarboxylate metabolism and one carbon pool by folate.