In enzymology, a 2-dehydropantolactone reductase (B-specific) () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are (R)-pantolactone and NADP<sup>+</sup>, whereas its 3 products are 2-dehydropantolactone, NADPH, and H<sup>+</sup>.
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 (R)-pantolactone:NADP<sup>+</sup> oxidoreductase (B-specific). Other names in common use include 2-oxopantoyl lactone reductase, 2-ketopantoyl lactone reductase, ketopantoyl lactone reductase, and 2-dehydropantoyl-lactone reductase (B-specific).