The grayish color of the stool is due to the lack of bile pigment in the stool, resulting in white stool, mostly due to mechanical obstruction of the biliary tract, such as bile duct stones, bile duct tumors or pancreatic head tumors. Bile duct stones can lead to obstruction of the bile ducts, resulting in localized pain and jaundice. Patients usually present with significant abdominal pain and fever, and if not treated promptly, they may also develop infectious toxic shock. White stools caused by bile duct stones are relatively rare in clinical practice, and only emergency surgery can save the patient’s life because of the obvious obstruction symptoms before turning white. The white stool is more often caused by tumors in the biliary tract or the head of the pancreas. The presence of tumors in these areas can lead to poor bile evacuation in the bile ducts, which causes progressive painless jaundice. Therefore, once the white stool or skin jaundice occurs, you should go to the hospital promptly to identify the specific cause of the biliary obstruction.