Abstract: Fatty liver hemorrhagic syndrome (FLHS) is a nutritional metabolism disease that often occurs in high-laying hens, and its clinical manifestations are mainly liver lipid deposition, sudden drop in egg production and acute death caused by layer hen lipid metabolism disorders, resulting in serious economic losses, which is a disease that needs to be focused on in intensive breeding at present.Gut microbiota, an important role in the growth and development of the body and immune metabolism, participate in the lipid synthesis and transport of the host, maintain the integrity of the intestinal barrier to avoid harmful substances from damaging the liver and affecting its function through blood circulation, and the amount and transformation direction of intestinal microbial metabolites will also have a good or bad impact on liver health.At present, it is believed that the pathogenesis of FLHS mainly includes nutrition, genetics, hormones, gut microbiota and other factors, and the "gut-liver axis" axis has also received extensive attention in the current treatment of liver diseases.Taking the gut microbiota as the starting point, by summarizing the common gut microbiota of laying hens and their functions related to lipid metabolism, the relevant research of gut microbiota in lipid metabolism and FLHS was reviewed, and the possible mechanism of action of gut microbiota and their metabolites in the process of FLHS development was introduced, in order to explain the possible pathogenesis of FLHS from the perspective of gut microbiota, find ways to prevent or treat FLHS by regulating gut microbiota in production practice, and promote the development of poultry farming.

Key words: fatty liver hemorrhagic syndrome(FLHS); gut microbiota; lipid metabolism