When gallstone patients go to the hospital or hospitalization, there are several gallstone patients together will wonder, the doctor told some gallstone patients to have ultrasound examination on it, some people have ultrasound and then have CT examination, some people also have MRI examination. Why is it that the imaging tests to be done are not the same for the same gallstone disease? To clarify this issue, we must first have a correct understanding and concept of the biliary system and “cholelithiasis”. The bile secreted by the liver cells is concentrated in dribs and drabs and is transported through a system of small and large ducts, which are called the biliary system, and is finally discharged into the duodenum. This duct system is called the biliary system. It is also those duct structures that carry the bile secreted by the liver to the duodenum. It generally consists of two parts: intrahepatic and extrahepatic bile ducts. The intrahepatic biliary tract has the bile ducts, left and right hepatic ducts; the extrahepatic biliary tract includes the common hepatic duct, common bile duct, cystic duct and gallbladder. The occurrence of stones in all parts of the biliary system can be called cholelithiasis, which can be seen as a generalized disease concept. In clinical practice, gallstone disease is often classified according to its location: intrahepatic bile duct stones, common bile duct stones, and gallbladder stones. Stones in different locations have different mechanisms of occurrence, affect the body differently, have different sensitivities to different imaging tests, and have different surgical treatments. It is very important to define the location of the stone before surgery, because it determines the specific plan of surgery. For gallbladder stones, the most sensitive test is ultrasound, followed by MRI and CT, so ultrasound is often sufficient for gallbladder stones; for common bile duct stones (especially small stones in the lower part of the bile duct), the most sensitive test is MRI, followed by CT and ultrasound; and for intrahepatic bile duct stones, ultrasound, CT and MRI are often required for comprehensive examination and analysis. Ultrasound is the basic imaging tool for gallstone disease. Therefore, doctors will choose different examination methods for different cases of cholelithiasis in order to obtain clear and detailed diagnostic results, which provide an important basis for scientific selection of the correct surgical plan.