In enzymology, 3-hydroxybutyryl-CoA dehydrogenase () is an enzyme that catalyzes the chemical reaction
The two substrates of this enzyme are ò-hydroxybutyryl-CoA and oxidised nicotinamide adenine dinucleotide phosphate (NADP<sup>+</sup>). Its products are acetoacetyl-CoA, reduced NADPH, and a proton.
This enzyme belongs to the family of oxidoreductases, to be specific 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 (S)-3-hydroxybutanoyl-CoA:NADP<sup>+</sup> oxidoreductase. Other names in common use include beta-hydroxybutyryl coenzyme A dehydrogenase, <small>L</small>-(+)-3-hydroxybutyryl-CoA dehydrogenase, BHBD, dehydrogenase, <small>L</small>-3-hydroxybutyryl coenzyme A (nicotinamide adenine, dinucleotide phosphate), <small>L</small>-(+)-3-hydroxybutyryl-CoA dehydrogenase, and beta-hydroxybutyryl-CoA dehydrogenase. This enzyme participates in benzoate degradation via coa ligation and butanoate metabolism.