In enzymology, a 16alpha-hydroxysteroid dehydrogenase () is an enzyme that catalyzes the chemical reaction
The 3 substrates of this enzyme are 16alpha-hydroxysteroid, NAD<sup>+</sup>, and NADP<sup>+</sup>, whereas its 4 products are 16-oxosteroid, NADH, NADPH, and H<sup>+</sup>.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD<sup>+</sup> or NADP<sup>+</sup> as acceptor. The systematic name of this enzyme class is 16alpha-hydroxysteroid:NAD(P)<sup>+</sup> 16-oxidoreductase. This enzyme is also called 16alpha-hydroxy steroid dehydrogenase.