The invention discloses a preparation method for high-purity opticity bergamio. The preparation method is a production process for preparing the high-purity opticity bergamio from canella natural opticity linalool and acetic anhydride through esterification reaction. The esterification reaction is performed in the presence of a catalyst potassium carbonate at the temperature of 65 and 85 DEG C and under reduced pressure for 25 to 35 hours, wherein the mass ratio of the linalool to the acetic anhydride is 1:1 to 1.5:1; and the using amount of the catalyst potassium carbonate is 0.615 to 0.667 percent of the weight of the reactant linalool. The prepared bergamio has opticity and the bergamio content is not less than 98.5 percent. By the method, the defect in preparation of bergamio raceme by using the linalool as a raw material is overcome; and technological support is provided for industrialized production of the opticity bergamio.