Belonging to the field of feed, the invention discloses a composite sheep feed and a preparation method thereof. The composite sheep feed comprises the following raw materials by weight: 60-70 parts of corn flour, 15-25 parts of peanut meal, 3-12 parts of rice bran, 4-12 parts of cottonseed meal, 3-9 parts of oat, 4-10 parts of soybean meal, 3-9 parts of millet, 2-8 parts of alfalfa meal, 1-3 parts of salt, 1-9 parts of semen raphani, 2-8 parts of coriander seed, 3-9 parts of carbonized sanguisorba root, 2-8 parts of cassia twig, 1-5 parts of perilla stem, 4-8 parts of magnolia officinalis, 3-9 parts of Fructus Arctii, 1-5 parts of Semen Alpiniae Katsumadai, and 4-10 parts of lotus leaf. The composite sheep feed prepared by the method provided by the invention has scientific formula and rich nutrition, can adapt to the growth and physiological characteristics of sheep, meets the nutritional components required by growth of sheep, promotes digestion and absorption, and also can enhance the immunity and resistance of sheep.