Fatty liver has an impact on liver function and can cause abnormal liver function, leading to elevated transaminases, bilirubin and other tests. In the early stage of simple fatty liver, there is no adverse effect on liver function because the degree of steatosis in liver cells is mild. If fatty liver reaches the middle or late stage, the liver cell tissue structure is damaged, causing steatohepatitis, liver function will be greatly affected, which can cause abnormal laboratory test indexes, such as transaminase, bilirubin, plasminogen and other test indexes are abnormal. Clinical manifestations are: fatigue, abdominal distension, loss of appetite, etc. Jaundice may occur in severe cases. Once fatty liver occurs, it should not be ignored because its early symptoms are not obvious, and it should be treated immediately under the guidance of doctors to avoid adverse consequences.