The invention discloses feed for promoting growth and development of broilers and a preparation method thereof. The feed is prepared from the following raw materials in parts by weight: 170-180 parts of dried sweet potato, 30-40 parts of corncob, 12-14 parts of dried distillers grain, 8-12 parts of red clover, 6-8 parts of egg-shell meal, 7-9 parts of sunflower meal, 10-15 parts of sargassum thunbergii, 5-7 parts of coconut shell flour, 4-5 parts of garlic powder, 15-20 parts of field-snail-meat, 20-30 parts of setosa immature stems, 16-18 parts of banana skin, 10-14 parts of ulva, 9-11 parts of kelp, 5-7 parts of chrysanthemum nankingense, 15-17 parts of water chestnut stems, 12-15 parts of coffee leaves, 2-3 parts of salt, 8-10 parts of Poria cocos, 7-9 parts of lycium barbarum, 3-5 parts of rhizoma curculiginis, 2-4 parts of isatis root, 1-3 parts of wahlenbergia marginata, 6-8 parts of fructus amomi, 0.5-0.7 part of choline chloride, 3-5 parts of medical stone powder and 7-9 parts of nutrition additives. The feed disclosed by the invention has the effects of regulating the metabolism of body cells, increasing the appetite of broilers, increasing the feed intake, improving the digestive absorption capacity and promoting growth and development, the weight of the broilers can be effectively increased, and the growth cycle of the broilers is shortened. Moreover, diseases of the broilers can be reduced, and the death rate of the broilers is reduced.