The invention discloses a feed for non-ruminant animals and a preparation method thereof. The feed comprises 30-60 parts of cassava, 20-30 parts of cassava stalks, 7-17 parts of pigeon pea stems and leaves, 1-2 parts of bacterial powder, 3-5 parts of yam beans, 2-5 stems and leaves of black nightshade, 2-4 parts of urea and 5-7 parts of beet pulp; wherein the stems and leaves of the black nightshade are soaked in water at the temperature of 45-75 DEG C; the pigeon pea stems and leaves and the yam beans are soaked in an ethanol water solution at 65-80 DEG C, and the ethanol water solution contains 5-10% of sodium formate. The silage provided by the invention has aromatic smell, is close to the raw materials in color and luster, is light brown after being dried, stems and leaves structure are kept well, and reaches an excellent grade. The dry matter content in the feed is 44-47%, the crude protein content is 5.5-6.5%, the soluble sugar content is 528-584 g/kgDM, the lactic acid content is 5-9%, the acetic acid content is 2-5%, the propionic acid content is 0.2-0.3%, butyric acid and hydrocyanic acid are not detected, the ammoniacal nitrogen content is as low as 0.023 g/kgDM, the pH is 3.09-3.80, the neutral detergent fiber content is 10-22%, the acid detergent fiber content is 5-12%, the feed quality is excellent, and the requirements of non-ruminant animals are met.