The present invention discloses a feed for meat chickens and a preparation method thereof. The feed comprises the following materials: 100-150 parts of soybean cake, 80-120 parts of corns, 80-100 parts of peanut shells, 50-80 parts of rice bran, 30-50 parts of shell powder, 5-10 parts of radix astragali multi-vitamins, 3-8 parts of talcum powder, 12-15 parts of methionine, 5-20 parts of calcium hydrogen phosphate, 2-5 parts of silkworm excrement, 2-10 parts of bone meal, 8-15 parts of mulberry leaf powder, 5-15 parts of gypsum, 3-8 parts of radix platycodonis, 7-13 parts of fructus amomi, 10-18 parts of seaweed meal, 5-12 parts of vegetable oil, 20-35 parts of grapefruit skin, 3-9 parts of trace elements, 4-10 parts of amino acids, 0.5-1 part of polypeptide, 1-3 parts of anhydrous sodium sulphate, 0.5-1.5 parts of edible salt, and 0.3-0.8 part of a microbial fermentation agent. The preparation method comprises premix preparing, resuscitating, expanding culturing, fermenting and filtering. The feed for the meat chickens has functions of improving immunity, and preventing bacteria and inflammation, can effectively reduce incidence of diseases in the meat chickens, controls deaths of sick chickens, has a good intestinal absorption effect, at the same time enhances appetite of the meat chickens and increases slaughter weight of the meat chickens.