Total Bile Acid (TBA) is an organic acid synthesized and secreted from the liver to the gallbladder as a raw material for cholesterol, and is a product of cholesterol catabolism. Total bile acid TBA is one of the liver function tests, and its increase can be seen in acute hepatitis and other diseases. Bile consists of bile acid salts, cholesterol, etc., and the most abundant substance is bile acid salts. Bile acid is mainly synthesized by the liver, and the total bile acid measurement can reflect the synthesis, uptake and secretion function of hepatocytes, and is related to the biliary excretion function. The normal value of this indicator is about 0-10 μmol/L, which may vary from laboratory to laboratory. Elevation of this index suggests the possible presence of acute or chronic active hepatitis, cirrhosis, hepatocellular carcinoma and other liver diseases, intrahepatic and extrahepatic bile duct obstruction and other biliary tract obstructive diseases. In addition, there may be a transient increase in serum total bile acid level after eating, but this change is physiologic and will recover on its own. Persistent elevation of total bile acids is recommended for prompt medical attention.