In enzymology, kynurenate-7,8-dihydrodiol dehydrogenase () is an enzyme that catalyzes the chemical reaction
The two substrates of this enzyme are 7,8-dihydro-7,8-dihydroxykynurenic acid and oxidised nicotinamide adenine dinucleotide (NAD<sup>+</sup>). Its products are 7,8-dihydroxykynurenic acid, reduced NADH, and a proton.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 7,8-dihydro-7,8-dihydroxykynurenate:NAD+ oxidoreductase. Other names in common use include 7,8-dihydro-7,8-dihydroxykynurenate dehydrogenase, and 7,8-dihydroxykynurenic acid 7,8-diol dehydrogenase. This enzyme participates in tryptophan metabolism.