The invention discloses a feed applicable to industrial aquaculture of tilapia, and a preparation method and a feeding method of the feed. The feed is prepared from corn protein powder, chicken powder, bean pulp, fermented rapeseed meal, fermented cottonseed meal, flour, soybean oil, fish oil, rice bran, mineral substances, vitamins and the like according to certain weight percent. The materials are prepared into granules by the steps of mixing, crushing, pelletizing, drying, screening and the like, and the granules are fed to the industrially cultivated tilapia according to the corresponding feeding method. The feed disclosed by the invention is made from the common materials, is low in cost, and is made by the simple and reliable preparation method; the raw materials are reasonable in proportion, and thus the feed can better meet the physiological needs of the industrially cultivated tilapia; the excrement of the tilapia is good in molding and unlikely to scatter, thus being discharged out of a culture system more easily. By virtue of the feeding method disclosed by the invention, ammonia and nitrogen emission can be reduced, the content of ammonia nitrogen and nitrite in a water body can be effectively reduced, and the resistance of the tilapia to streptococcus is enhanced.