Hepatobiliary surgery is complex and generally involves a number of disease- and surgery-related tests and labs in addition to the routine tests necessary for surgery. However, patients are confused about many of these tests and do not know why or what they mean. We have introduced some routine examinations and their significance earlier, and the following is a brief introduction to some special examinations required before hepatobiliary surgery: 1. plain CT and enhanced CT of the liver: CT is of great significance for the judgment of hepatobiliary diseases, and enhanced CT has high sensitivity and specificity for identifying the nature of liver tumors, especially for the characterization and localization of some common liver tumors such as hepatocellular carcinoma and hepatic hemangioma. It is especially useful for the characterization and localization of some common liver tumors such as hepatocellular carcinoma and hepatic hemangioma. MRI and enhanced MRI: MRI has special value in diagnosing hepatobiliary diseases, for example, MRCP (Magnetic Resonance Cholangiopancreaticography) can show the alignment of pancreaticobiliary ducts, whether there is stenosis or dilatation, the location and nature of the disease, and can indirectly determine stones or tumors; MRI, especially Pulmonary Enhanced MRI, has special significance in identifying hepatocellular carcinoma and some benign tumors. 3.Ultrasound and ultrasonography: Ultrasound has been used as the first choice for screening and diagnosis of hepatobiliary diseases, with the advantages of convenience and non-invasiveness. The application of ultrasonography has improved the sensitivity and specificity of ultrasound in determining the nature of hepatobiliary diseases, especially hepatobiliary tumors, and puncture biopsy can be performed under ultrasound guidance for pathological examination. 4.ERCP: endoscopic cholangiopancreatography has its irreplaceable role as an invasive examination. It is complementary to MRCP. ERCP has more obvious advantages in determining the disease of the end of the common bile duct, and biopsy and treatment can be performed at the same time, although invasive, but its role cannot be ignored. 5.PET-CT whole body PET-CT examination: it is more used to diagnose the site, nature and whether the tumor is metastatic or not, with higher sensitivity and specificity, although it is expensive, its role is irreplaceable for specific patients. All of these tests are common tests needed to determine the nature of disease and evaluate the surgery before surgery, especially hepatobiliary surgery.