(R)-1,3-butanediol is an important chiral building block and template in asymmetric synthesis.Carbonyl reductase catalyzed asymmetric reduction of 4-hydroxy-2-butanone is an effective way for large scale production of(R)-1,3-butanediol.In this paper,culture conditions of Candida krusei ZJB 09162 producing carbonyl reductase were optimized as follows: glucose 50.0 g/L,yeast extract 50.0 g/L,(NH4)2HPO4 2.5 g/L,KH2PO4 2.5 g/L,NaCl 1.0 g/L,initial pH 6.0,medium volume 12%,inoculum size 4%.Under these conditions,the yield of(R)-1,3-butanediol reached 85%,with an optical purity of 99% e.e.