In enzymology, an aldose 1-dehydrogenase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are D-aldose and NAD<sup>+</sup>, whereas its 3 products are D-aldonolactone, NADH, 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 D-aldose:NAD<sup>+</sup> 1-oxidoreductase. Other names in common use include aldose dehydrogenase, and dehydrogenase, D-aldohexose.