In enzymology, a glycine reductase () is an enzyme that catalyzes the chemical reaction
The 4 substrates of this enzyme are acetyl phosphate, NH<sub>3</sub>, thioredoxin disulfide, and H<sub>2</sub>O, whereas its 3 products are glycine, phosphate, and thioredoxin.
This enzyme belongs to the family of oxidoreductases, to be specific, those acting on X-H and Y-H to form an X-Y bond with a disulfide as acceptor. The systematic name of this enzyme class is acetyl-phosphate ammonia:thioredoxin disulfide oxidoreductase (glycine-forming).