In enzymology, a long-chain-fatty-acyl-CoA reductase () is an enzyme that catalyzes the chemical reaction
The 3 substrates of this enzyme are long-chain aldehyde, CoA, and NADP<sup>+</sup>, whereas its 3 products are long-chain acyl-CoA, NADPH, and H<sup>+</sup>.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is long-chain-aldehyde:NADP+ oxidoreductase (acyl-CoA-forming). Other names in common use include acyl-CoA reductase, and acyl coenzyme A reductase.