In enzymology, a phloretin hydrolase (EC 3.7.1.4) is an enzyme that catalyzes the chemical reaction

phloretin + H₂O ${\displaystyle \rightleftharpoons }$ phloretate + phloroglucinol

Thus, the two substrates of this enzyme are phloretin and H₂O, whereas its two products are phloretate and phloroglucinol.

This enzyme belongs to the family of hydrolases, specifically those acting on carbon–carbon bonds in ketonic substances. The systematic name of this enzyme class is 2',4,4',6'-tetrahydroxydehydrochalcone 1,3,5-trihydroxybenzenehydrolase. This enzyme is also called lactase-phlorizin hydrolase.