In enzymology, a methylglyoxal reductase (NADPH-dependent) (EC 1.1.1.283) is an enzyme that catalyzes the chemical reaction

lactaldehyde + NADP⁺ ${\displaystyle \rightleftharpoons }$ methylglyoxal + NADPH + H⁺

Thus, the two substrates of this enzyme are lactaldehyde and NADP⁺, whereas its 3 products are methylglyoxal, NADPH, 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 lactaldehyde:NADP⁺ oxidoreductase. Other names in common use include lactaldehyde dehydrogenase (NADP⁺), and Gre2.

• Murata K, Fukuda Y, Simosaka M, Watanabe K, Saikusa T, Kimura A (1985). "Metabolism of 2-oxoaldehyde in yeasts. Purification and characterization of NADPH-dependent methylglyoxal-reducing enzyme from Saccharomyces cerevisiae". Eur. J. Biochem. 151 (3): 631–636. doi:10.1111/j.1432-1033.1985.tb09151.x. PMID 3896793.
• Johnston M, Chitnis PR, Kohl DH (2003). "Associating protein activities with their genes: rapid identification of a gene encoding a methylglyoxal reductase in the yeast Saccharomyces cerevisiae". Yeast. 20 (6): 545–554. doi:10.1002/yea.979. PMID 12722185.