The invention discloses a natural food and a preparation method thereof, the natural food comprises the following raw materials in parts by weight: 1-10 parts of coarse cereals, 0.5-2 parts of mushroom, 0.2-2.4 parts of fruits and vegetables, 0.8-2 parts of seaweeds, 1 to 3 parts of nuts, 1 to 5 parts of beans and 1.2 to 2 parts of additives. By adding the coarse cereals and the fruits and vegetables rich in vitamins, the nuts rich in microelements such as calcium, iron, zinc and selenium, and the beans and the mushroom providing rich proteins, intake requirements of a human body for nutritional ingredients such as the vitamins, copper, iron, selenium, zinc, calcium, and fibers can be met, the problem of damage to the human body caused by single food lack of nutritional ingredients is solved, and the purpose of balanced nutrition is achieved.