In enzymology, an aldehyde dehydrogenase [NAD(P)+] () is an enzyme that catalyzes the chemical reaction
The 4 substrates of this enzyme are aldehyde, NAD<sup>+</sup>, NADP<sup>+</sup>, and H<sub>2</sub>O, whereas its 4 products are acid, NADH, NADPH, and H<sup>+</sup>.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is aldehyde:NAD(P)+ oxidoreductase. Other names in common use include aldehyde dehydrogenase [NAD(P)+], and ALDH. This enzyme participates in 5 metabolic pathways: glycolysis / gluconeogenesis, histidine metabolism, tyrosine metabolism, phenylalanine metabolism, and metabolism of xenobiotics by cytochrome p450.
As of late 2007, 4 structures have been solved for this class of enzymes, with PDB accession codes , , , and .