The application discloses feed for improving the digestibility of penaeus vannamei and a preparation method therefor and application of the feed. The feed consists of grain powder, cake meal, calciumcarbonate, zeolite, radix isatidis extract, silkworm chrysalis, an antioxidant, a mold inhibitor, rhizoma atractylodis extract, rhizoma curcumae longae extract, nucleotide, lysozyme (LSZ), common cyanotis root extract, cellulase, herba leonuri extract, alpha-amylase, rhizoma alismatis extract and ulva lactuca extract. The feed is not easy to go moldy or bad, has no caking and a peculiar smell, hashigh stability in water, does not scatter within 3-5h, has no residues, has no side effects, destroys a cell outer membrane of vibrio, and can kill vibrio parahaemolyticus; the survival rate of the penaeus vannamei is 74%-79%, and is increased by 10%-17%; body length is increased by 20%-50%; the reproductive capacity is improved; the feed has good palatability; the digestibility is improved; thepenaeus vannamei grows fast, is 16-24cm long and weighs 42-52g; and the feed is easy to industrialize, and has a broad application prospect.