In enzymology, a (R,R)-butanediol dehydrogenase (EC 1.1.1.4) is an enzyme that catalyzes the chemical reaction

(R,R)-butane-2,3-diol + NAD⁺ ${\displaystyle \rightleftharpoons }$ (R)-acetoin + NADH + H⁺

Thus, the two substrates of this enzyme are (R,R)-butane-2,3-diol and NAD⁺, whereas its 3 products are (R)-acetoin, NADH, and H⁺.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD⁺ or NADP⁺ as acceptor. The systematic name of this enzyme class is (R,R)-butane-2,3-diol:NAD⁺ oxidoreductase. Other names in common use include butyleneglycol dehydrogenase, D-butanediol dehydrogenase, D-(−)-butanediol dehydrogenase, butylene glycol dehydrogenase, diacetyl (acetoin) reductase, D-aminopropanol dehydrogenase, D-aminopropanol dehydrogenase, 1-amino-2-propanol dehydrogenase, 2,3-butanediol dehydrogenase, D-1-amino-2-propanol dehydrogenase, (R)-diacetyl reductase, (R)-2,3-butanediol dehydrogenase, D-1-amino-2-propanol:NAD⁺ oxidoreductase, 1-amino-2-propanol oxidoreductase, and aminopropanol oxidoreductase. This enzyme participates in butanoic acid metabolism.