High bilirubin may be due to obstructive jaundice, hemolytic jaundice or hepatocellular jaundice, etc. The degree of elevation of bilirubin varies with different causes. 1. Obstructive jaundice: after the obstruction of biliary system caused by various reasons, the conjugated bilirubin which has been generated in the liver system can not enter into the intestinal cavity smoothly and seeps into the bloodstream, therefore, the serum conjugated bilirubin is obviously elevated, and part of the unconjugated bilirubin can not be converted into the conjugated bilirubin in time but is manifested to be elevated, and the total bilirubin is elevated as well. 2. Hemolytic jaundice: when hemolysis occurs in the body, the destruction of red blood cells can directly increase the unconjugated bilirubin in the blood, so the serum unconjugated bilirubin is obviously elevated, and the conjugated bilirubin can be mildly elevated due to the increase in the conversion of unconjugated bilirubin, so the total bilirubin is also elevated. 3. Hepatocellular jaundice: when hepatocellular injury is caused by various reasons, the ability of the liver to take up unconjugated bilirubin in the blood decreases, so the unconjugated bilirubin in the serum is moderately elevated. Meanwhile, the conjugated bilirubin that has already been synthesized by the liver may leak into the blood due to the hepatocellular injury, so the conjugated bilirubin of the serum is also moderately elevated, and total bilirubin is also elevated. There are many other reasons for high bilirubin, and it is recommended to actively seek medical advice and standardized treatment to avoid unauthorized treatment to delay the condition or cause adverse consequences.