Patients with elevated bilirubin are considered to have elevated bilirubin if their total bilirubin is 17.1 μmol/L or higher. However, if the patient’s bilirubin is between 17.1 and 34.2 μmol/L, clinically it is also called occult jaundice, which means that although the patient has elevated bilirubin, the patient’s skin and sclera are generally not detected by the naked eye. At this time, the patient should further look for elevated glutathione and glutamic oxalacetic aminotransferase. If there is elevation, liver function damage should be considered, and the patient needs active liver protection treatment. If the patient’s bilirubin, especially total bilirubin, exceeds 34.2 μmol/L or more, and direct bilirubin is mainly elevated, this condition is mostly considered to be caused by obstructive factors. Patients need to further investigate the upper abdominal ultrasound or MRCP bile duct imaging to see the cause and location of the obstruction. If total bilirubin and indirect bilirubin are predominantly elevated, it is possible that the jaundice is caused by hepatocellular necrosis.