The invention relates to the technical field of feeds, in particular to a cow feed for preventing and treating diarrhea. The cow feed consists of the following substances in parts by weight: 45-55 parts of corn flour, 45-55 parts of flour, 15-25 parts of glucose, 25-45 parts of soybean meal, 18-25 parts of germ meal, 1-3 parts of calcium carbonate, 5-8 parts of semen myristicae, 3-6 parts of lalang grass rhizomes, 7-12 parts of hairyvein agrimonia herbs, 15-25 parts of oat, 8-12 parts of bran, 8-12 parts of coconut oil cakes, 3-6 parts of amber, 8-12 parts of sugar residues, 5-12 parts of radix codonopsis, 3-5 parts of bighead atractylodes rhizomes, 8-12 parts of poria, 5-8 parts of cortex magnoliae officinalis, 8-12 parts of rhizoma corydalis, 3-8 parts of radix bupleuri, 8-12 parts of dried orange peel, 5-8 parts of radix puerariae, 5-12 parts of inula helenium, 8-12 parts of garlic, 9-15 parts of asiatic cornelian cherry fruits, 15-20 parts of Chinese yams, 5-8 parts of smoked plums, 5-10 parts of licorice roots, 5-8 parts of radix scrophulariae, 8-12 parts of geranium wilfordii, and 5-10 parts of halloysitum rubrum. According to the cow feed, provided by the invention, various traditional Chinese medicines and plants are added and mixed, so that the diarrhoea can be effectively prevented, and when being used for treating the diarrhoea, the feed has the advantages of taking effect quickly, and being true in treatment effects, few in side effects and low in drug residues of livestock products, drug resistance is not liable to cause, and safety of people and livestock is guaranteed.