The invention discloses a poult compound feed for promoting development of digestive tracts of chickens and a preparation method thereof. The poult compound feed is prepared from corn, soybean meal, corn protein powder, specific raw material rich in insoluble fiber, and poult compound premix, wherein the content of the corn is 55-68 parts, the content of the soybean meal is 20-28 parts, the content of the corn protein powder is 3-10 parts, the content of the specific raw material rich in insoluble fiber is 3-6 parts, the content of soybean oil is 0-3 parts, and the content of the poult compound premix is 3-6 parts. The preparation method comprises the following steps of: firstly, crushing the specific raw material rich in insoluble fiber to a product with a particle size of 2-4 mm; then, crushing the corn and the soybean meal to a product with a particle size of 1-1.5 mm; and uniformly mixing the raw materials in proportion so as to obtain a crushed material with a particle size of 1.5-3.0 mm finally. The poult compound feed can significantly improve the development of digestive organs such as stomachs, intestinal tracts and the like of poults, improve the digestive utilization rate of feeds, improve the production performance of chicken, improve the physical conditions of poults, and reduce the morbidity of diseases of digestive tracts and the death rate.