Fuente: WIPO "dairy products" The invention relates to the technical field of dairy products, in particular to a preparation method of milk rich in dietary fibers and the milk prepared by the preparation method. According to the milk preparation method disclosed by the invention, an ultrafiltration technology and a beta-galactosidase enzymolysis process are combined, so that the protein and calcium contents of the milk are improved, the yield of generating dietary fiber GOS by utilizing lactose in the milk is greatly improved, the dietary fiber content in the milk is remarkably improved, the extremely low lactose content is realized, and the milk has a good market prospect. Therefore, the native high-power nutritional milk with high protein, high calcium and high dietary fiber is prepared, the requirements of consumers on nutrition and health can be better met, and the high-power nutritional milk has better taste and flavor.