An elevated AST or ALT value with a decreased ratio usually represents impaired liver function, such as hepatitis, cirrhosis, and hepatocellular carcinoma. AST and ALT are two indicators to test liver function, AST refers to Menthol Aminotransferase and ALT is Alanine Aminotransferase.The normal values of AST and ALT are 0 to 40 U/L, if both AST and ALT values are in the normal range. A decrease in the ratio may be of little significance. 1. Viral hepatitis: mainly related to hepatitis virus infection, infectious, need to do hepatitis B five, hepatitis B virus DNA quantitative and other tests, if the liver function is damaged, need to actively carry out hepatoprotective and antiviral treatment. 2. Liver cirrhosis, liver cancer: mainly related to long-term excessive alcohol abuse, viral infection, it is recommended to do blood test, liver fibrosis and other indicators, as well as liver, gallbladder, pancreas and spleen ultrasound and other tests to clarify the diagnosis. Low AST/ALT often suggests that liver function is impaired, and patients should go to the hospital in time to find out the cause of the problem and treat the symptoms in time.