The invention aims at providing high-purity and high-content zinc bacitracin. A preparation method of the zinc bacitracin comprises the following steps: S1, mixing zinc bacitracin powder and adhesive, adding water for diluting, regulating the pH value to be 5-8, granulating at the temperature of 10-25 DEG C, drying at the temperature ranging from -20 DEG C to 5 DEG C, sieving, and spraying a micro permeable membrane, so as to obtain bacitracin micro capsules; S2, regulating the pH value of an inorganic zinc aqueous solution to be 8-11, gradually adding the prepared bacitracin micro capsules, after salifying, regulating the pH value to be 5-7 with inorganic acid, stirring, and standing; and S3, separating, drying, and smashing, so that the zinc bacitracin is obtained.