The invention discloses a preparation method of yeast. The preparation method comprises the following steps: successively weighing the following solid substances: steamed bread residue, Chinese koji, high-activity yeast, monocrystal rock sugar and Daqu, wherein the mass ratio of steamed bread residue to Chinese koji to high-activity yeast to monocrystal rock sugar to Daqu is 8:5:3:2:2; weighing liquids including purified water and glutinous rice wine to guarantee that mass ratio of purified water to glutinous rice wine is 5:3; uniformly mixing the liquids and the solid substances according to a certain ratio, putting the mixture into a fermentation tank and fermenting at the constant temperature of 28-30 DEG C for 30 min; successively adding glutinous rice flour or purified water by four steps into the fermented substance, successively fermenting, making the yeast into a pancake, and air-drying in the shade to directly obtain the white, slightly grey yeast which is shaped as glutinous rice flour and has strong mellow fragrance. The yeast is cultivated through five-step fermentation. The yeast is shaped as glutinous rice flour and is convenient to use and store, and the preparation technology is simple.