The invention mainly relates to the technical field of beverage processing, and discloses a corn liquor preparation method, which comprises the following steps of germination of corns, preparation ofcorn bran and corn leaves, material mixing, saccharification, lactic acid fermentation, yeast fermentation and centrifugation. The corn liquor preparation method is simple and is convenient to operate. By adopting the corn liquor preparation method, obtained corn liquor is light green in color and lustre, rich in flavor, mellow in taste and rich in nutrition, and is capable of promoting blood circulation, protecting heart and cerebral vessels, expelling toxin, maintaining facial beauty, resisting oxidation, resisting ageing, and resisting and inhibiting the cancer; by adding a sodium selenitesolution in the corns, germination is promoted, so that inorganic selenium is changed into organic selenium, rich low molecular nutritional components can be produced at the same time, absorption is promoted, and the flavor of the corn liquor is improved; and by adding the fermented corn bran and corn leaves, the nutritional components and the flavor of the corns are increased, the health care function is strengthened, the wastes are turned into wealth, and the economic income of corn planting is increased.