Alanine aminotransferase 51U/L is on the high side. Alanine aminotransferase is an important indicator of liver function, with normal values ranging from 5 to 40 U/L for men and from 5 to 35 U/L for women; therefore, the results of alanine aminotransferase 51U/L are higher than normal. Temporary elevation of alanine aminotransferase may be caused by strenuous exercise, excessive fatigue, alcohol consumption, staying up late, eating greasy food, or taking medication for liver injury before the test. If the patient has no other uncomfortable symptoms, usually there is no problem, usually should pay more attention to rest, eat a light diet, avoid spicy, greasy food, etc., when using hepatotoxic drugs should be regularly monitored liver function. If the patient combines with jaundice, fatigue, fever, pain in the liver area and other symptoms, it may be related to acute and chronic viral hepatitis, cirrhosis, alcoholic liver disease, liver cancer and so on, which will lead to the elevation of this index. If the test result of alanine transferase is abnormal, it is recommended to consult a doctor in time to clarify the cause of the disease and then carry out targeted treatment or therapy under the guidance of the doctor.