In enzymology, cinnamyl-alcohol dehydrogenase () is an enzyme that catalyzes the chemical reaction
The two substrates of this enzyme are cinnamyl alcohol and oxidised nicotinamide adenine dinucleotide phosphate (NADP<sup>+</sup>). Its products are cinnamaldehyde, reduced NADPH, and a proton.
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 cinnamyl-alcohol:NADP<sup>+</sup> oxidoreductase. Other names in common use include cinnamyl alcohol dehydrogenase, and CAD. This enzyme participates in phenylpropanoid biosynthesis.
As of late 2007, 4 structures have been solved for this class of enzymes, with PDB accession codes , , , and .