Most stools appear off-white due to a lack of bile pigment in the stool, which turns yellow stools off-white. The cause of white stool is related to biliary obstruction, when bile cannot be properly drained into the intestinal cavity, the stool will appear white. Causes of biliary obstruction include stones and tumors. In addition to causing localized bile to fail to empty into the intestine, stones often cause other complications of cholangitis such as abdominal pain, fever, chills, and jaundice. Since cholangitis often endangers patients’ lives and can easily lead to infectious toxic shock if not treated properly, bile duct stones are not difficult to diagnose. In case of neoplastic diseases, such as cholangiocarcinoma or jugular carcinoma, the blockage of the bile duct caused by the tumor is mostly a progressive lesion, and the patient will not experience significant pain. Only when the patient has significant jaundice will the stool appear white. Therefore, when there is obvious jaundice with white stools, imaging tests such as ultrasound, MRI or CT should be performed to test whether a tumor is present near the bile ducts or pancreas.