In enzymology, an estradiol 17beta-dehydrogenase (EC 1.1.1.62) is an enzyme that catalyzes the chemical reaction

estradiol-17beta + NAD(P)+ ${\displaystyle \rightleftharpoons }$ estrone + NAD(P)H + H⁺

The 3 substrates of this enzyme are estradiol-17beta, NAD⁺, and NADP⁺, whereas its 4 products are estrone, NADH, NADPH, and H⁺.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD⁺ or NADP⁺ as acceptor. The systematic name of this enzyme class is estradiol-17beta:NAD(P)⁺ 17-oxidoreductase. Other names in common use include 20alpha-hydroxysteroid dehydrogenase, 17beta,20alpha-hydroxysteroid dehydrogenase, 17beta-estradiol dehydrogenase, estradiol dehydrogenase, estrogen 17-oxidoreductase, and 17beta-HSD. This enzyme participates in androgen and estrogen metabolism.

As of late 2007, 29 structures have been solved for this class of enzymes, with PDB accession codes 1A27, 1BHS, 1DHT, 1EQU, 1FDS, 1FDT, 1FDU, 1FDV, 1FDW, 1GZ6, 1I5R, 1IKT, 1IOL, 1JTV, 1QYV, 1QYW, 1QYX, 1S1P, 1S1R, 1S2A, 1S2C, 1XF0, 1YB1, 1ZQ5, 2F38, 2FGB, 2HQ1, 2PD6, and 3DHE.

• Kautsky MP, Hagerman DD (1970). "17β-Estradiol Dehydrogenase of Ovine Ovaries". J. Biol. Chem. 245 (8): 1978–84. doi:10.1016/S0021-9258(18)63194-1. PMID 4314937.
• Langer LJ, Alexander JA, Engel LL (1959). "Human Placental Estradiol-17β Dehydrogenase. II. Kinetics and substrate specificities". J. Biol. Chem. 234 (10): 2609–14. doi:10.1016/S0021-9258(18)69746-7. PMID 14413943.