In enzymology, sorbitol-6-phosphate dehydrogenase () is an enzyme that catalyzes the chemical reaction
The two substrates of this enzyme are D-sorbitol 6-phosphate and oxidised nicotinamide adenine dinucleotide (NAD<sup>+</sup>). Its products are fructose 6-phosphate (shown in its open-chain form), reduced NADH, and a proton.
This enzyme belongs to the family of oxidoreductases, specifically 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 D-sorbitol-6-phosphate:NAD<sup>+</sup> 2-oxidoreductase. Other names in common use include ketosephosphate reductase, ketosephosphate reductase, D-sorbitol 6-phosphate dehydrogenase, D-sorbitol-6-phosphate dehydrogenase, sorbitol-6-P-dehydrogenase, and D-glucitol-6-phosphate dehydrogenase. This enzyme participates in fructose and mannose metabolism.