The diagnosis of benign and malignant cholangiocarcinomas can be made with the help of tumor marker tests, imaging tests such as enhanced CT and MRI, and performing pathological biopsies. Since the bile duct itself has a small diameter, both benign and malignant tumors can cause clinical manifestations of bile duct obstruction such as fever, epigastric discomfort, jaundice, and so on. 1. First of all, we can check with the help of blood tumor markers, the tumor markers in the blood of patients with malignant tumors may rise significantly, especially CA-199. 2. Imaging examination, commonly used means of examination include enhanced CT and magnetic resonance, through imaging means to identify the imaging performance of the tumor, whether it invades the surrounding tissue structure, etc. 3. Pathological biopsy is the most accurate means to determine the benign or malignant nature of the mass by obtaining the tissue from the patient through surgery and conducting pathological examination. Patients should consult the doctor in time, complete the relevant examinations, make a clear diagnosis, and then adopt corresponding treatment programs.