Abstract: The invention relates to a method for producing the optically active alkanols of formula (I), wherein n is an integer of from 0 to 5; Cyc represents an optionally substituted, mononuclear or polynuclear, saturated or unsaturated, carbocylic or heterocyclic ring, and R1 represents halogen, SH, OH, NO2, NR2R3 or NR2R3R4+X?, wherein R2, R3 and R4 independently represent H or a lower alkyl or lower alkoxy group and X? represents a counterion. According to the invention, an enzyme (E) selected from the groups of dehydrogenases, aldehyde reductases and carbonyl reductases is incubated in a medium containing the alkanone of formula (II), wherein n, Cyc and R1 are defined as above, in the presence of reduction equivalents.