Chiral alcohols are useful intermediates for many pharmaceuticals and chemicals. Enzymatic asymmetric reduction of prochiral carbonyl compounds is a promising method for producing chiral alcohols. There have been many attempts to construct bioreduction systems for the industrial production of chiral alcohols. This review focuses on the establishment of a novel bioreduction system using an Escherichia coli transformant co-expressing genes for carbonyl reductase and cofactor-regeneration enzyme. This bioreduction system could be useful as an all-purpose catalyst for asymmetric reduction reactions.