Disclosed are a method for producing ethanol and a device for producing ethanol that are suitable to the recycled use of an enzyme.The device is configured from: a vacuum distillation tower (11) into which an ethanol-fermented liquid generated by saccharification fermentation of a biomass starting material is introduced, and with the interior in a state that is at a lower pressure than atmospheric pressure, that subjects the ethanol-fermented liquid to distillation, distilling ethanol vapor that contains water vapor, and removing as a bottom product the enzyme-containing concentrated waste liquid that is roused for saccharification fermentation of the biomass starting material; and a fractionating tower (12) for fractionating the ethanol vapor distilled from the vacuum distillation tower (11). In this case, the energy of the ethanol vapor can be more efficiently taken advantage of if the device is provided with a first compressor (16) that adiabatically compresses the ethanol vapor distilled from the vacuum distillation tower (11), and the ethanol vapor adiabatically compressed by the first compressor (16) is introduced into the fractionating tower (12).