In enzymology, choline dehydrogenase () is an enzyme that catalyzes the chemical reaction
The two substrates of this enzyme are choline and an electron acceptor. Its products are glycine betaine aldehyde and the corresponding reduced acceptor. The enzyme is a quinoprotein.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with other acceptors. The systematic name of this enzyme class is choline:acceptor 1-oxidoreductase. Other names in common use include choline oxidase, choline-cytochrome c reductase, choline:(acceptor) oxidoreductase, and choline:(acceptor) 1-oxidoreductase. This enzyme participates in glycine, serine and threonine metabolism. It employs one cofactor, PQQ.