NOVELTY - Preparing avilamycin premix comprises (i) taking MCCC1A01659-Streptomyces viridochromogenes, carrying out seed culture, and fermenting to obtain avilamycin fermentation liquor; (ii) subjecting the fermentation liquor to high-pressure filtration, and separating out filtered liquid to obtain avilamycin filter cake; (iii) subjecting the filter cake to flash evaporation drying process to obtain avilamycin mycelium dry product, and detecting avilamycin content; (iv) crushing; and (v) adding the powder carrier to the fine powder to regulate desired concentration, and uniformly mixing.    USE - The method is useful for preparing avilamycin premix (claimed).    ADVANTAGE - The method: does not need to refine and extract avilamycin; does not consume organic solvents and acid and alkali; and has less pollution on the environment; achieves imported veterinary standards of the product with uniform quality and stability; does not generate dangerous solid wastes including antibiotic bacterium residues during the production and preparation process; and reduces production cost, environmental pollution and post-treatment cost.    DETAILED DESCRIPTION - Preparing avilamycin premix comprises (i) taking MCCC1A01659-Streptomyces viridochromogenes with preservation number of 1A01659, carrying out seed culture, inoculating the strain with 5-10% inoculum size in a fermentation tank for fermenting to obtain avilamycin fermentation liquor containing 3000-7000 mu g/ml avilamycin content; (ii) subjecting the avilamycin fermentation liquor to high-pressure filtration under 1-5 Mpa pressure, and separating out 85-95% filtered liquid to obtain avilamycin filter cake; (iii) subjecting the filter cake to flash evaporation drying process, controlling air inlet temperature to 130-170 degrees C and air outlet temperature to 70-90 degrees C under gas flow of 8-10 m3/minute to obtain avilamycin mycelium dry product, and detecting avilamycin content; (iv) crushing the avilamycin dry powder into avilamycin mycelium fine powder; and (v) adding the powder carrier to the avilamycin mycelium fine powder to regulate desired concentration, and uniformly mixing to obtain avilamycin premix.