VLCFAs are biosynthesized by an endoplasmic reticulum associated enzyme system, referred to as fatty acid elongase. Fatty acid elongase generates VLCFAs by elongating 18C fatty acids. The enzymatic machinery of fatty acid elongation is believed to be composed of 3-ketoacyl-CoA synthase, 3-ketoacyl-CoA reductase, 3-hydroxyacyl-CoA dehydratase, and enoyl-CoA reductase. However, the insoluble nature of the fatty acid elongase system has hampered efforts to purify the system and to identify the genes that encode the component proteins. In the current study a candidate gene cloning approach was used to demonstrate that the previously defined gl26 gene of maize encodes a predicted enoyl-CoA reductase (ECR). Based on the phenotypes of existing and newly isolated gl26 mutants, the GL26 protein is required for the normal accumulation of cuticular waxes (CWs). The specific alterations in the composition of the CWs and the transcripts of gl26 gene that accumulate on gl26 mutants are consistent with the GL26 protein being a ECR. Because some of the gl26 mutants exhibit conditional lethality, we conclude that ECR activity is essential in maize. Using the similar methods, two candidates of 3-hydroxyacyl-CoA dehydratase (HCD) were identified in maize.