Distiller's grains,a kind of ethanol production industry by-products,which contain abundant nutri-ents,such as high crude protein content,complete amino acids and rich bioactive substances,and can be used as an excellent unconventional feed resource.However,fresh distiller's grains were easy to deteriorate and dif-ficult to preserve,and contain higher content of anti-nutritional factors,such as crude fiber,resulting in the ap-plication of fresh distiller's grains in monogastric animals is limited.Microbial fermentation can effectively re-duce the content of crude fiber,increase the content of crude protein and the utilization rate of phosphorus,and improve the utilization efficiency of distiller's grains.Therefore,the microbial fermentation of distiller's grains into high quality biological feed is not only beneficial to promote its feed utilization,but also to save conventional feed resources such as corn and soybean meal and reduce breeding costs.This paper reviews the resources,nutritional characteristics and composition of distiller's grains,the production process of fermented distiller's grains and the application of fermented distiller's grains in swine and chicken production,to provide reference for the application of fermented distiller's grains as feed in swine and chicken production.[Chinese Journal of Animal Nutrition,2024,36(4):2188-2198]