In enzymology, a L-amino-acid dehydrogenase () is an enzyme that catalyzes the chemical reaction
The 3 substrates of this enzyme are L-amino acid, H<sub>2</sub>O, and NAD<sup>+</sup>, whereas its 4 products are 2-oxo acid, NH<sub>3</sub>, NADH, and H<sup>+</sup>.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH<sub>2</sub> group of donors with NAD<sup>+</sup> or NADP<sup>+</sup> as acceptor. The systematic name of this enzyme class is L-amino-acid:NAD+ oxidoreductase (deaminating).