In enzymology, a 2'-hydroxyisoflavone reductase (EC 1.3.1.45) is an enzyme that catalyzes the chemical reaction

vestitone + NADP⁺ ${\displaystyle \rightleftharpoons }$ 2'-hydroxyformononetin + NADPH + H⁺

Thus, the two substrates of this enzyme are vestitone and NADP⁺, whereas its 3 products are 2'-hydroxyformononetin, NADPH, and H⁺.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is vestitone:NADP+ oxidoreductase. Other names in common use include NADPH:2'-hydroxyisoflavone oxidoreductase, isoflavone reductase, and 2',7-dihydroxy-4',5'-methylenedioxyisoflavone reductase.

• Tiemann K, Hinderer W, Barz W (1987). "Isolation of NADPH:isoflavone oxidoreductase, a new enzyme of pterocarpan biosynthesis in cell suspensions of Cicer arietinum". FEBS Lett. 213 (2): 324–328. doi:10.1016/0014-5793(87)81515-6.