Bad liver function may be caused by bad living and eating habits, fatty liver, viral hepatitis, drug hepatitis and so on. 1. Bad life and dietary habits: often stay up late, overwork, long-term heavy drinking leads to liver function damage, causing bad liver function. 2. Fatty liver: lack of exercise, diet too greasy, etc. lead to excessive obesity, induced fatty liver damage to the liver, resulting in poor liver function. 3. Viral hepatitis: such as viral hepatitis B, hepatitis C, hepatitis E and so on, which leads to liver cell damage and causes bad liver function. 4. Drug hepatitis: taking certain drugs destroys liver cells, leading to liver damage and bad liver function. Liver function is not good, it is recommended to consult a doctor in time to find out the cause of the disease, and follow the doctor’s instructions for treatment.