A total of 72 cases of internal biliary drainage procedure has been done percutaneously at Department of Radiology, Seoul National University Hospital for recent 4 and half years since August 1981. Five different types of internal drainage including endoprosthesis were applied to various conditions with different obstruction levels, The different method of procedure in each type of internal drainage was described and the results were analysed. 1. Among the clinical diagnosis in 72 cases, carcinoma of bile duct was in 37 cases as the most frequent one. The next was pancreas head carcinoma in 16 cases, followed by metastatic carcinoma and other diseases. 2. Type internal drainage, classical internal and external type with distal end in duodenum, was applied in 43 cases as the most common one. Type ll, modifecation of type l with distal end in CBD, was applied in 17 cases. Type lll, endoprosthesis distal end into duodenum, was applied in 7 cases. Type IV, endoprosthesis just acro s the obstruction in bile duct, was applied in 2 cases, Type V, combined type of any internal drainage with external drainage, was applied in 3 cases. 3. According to various obstruction level. preferred type could be selected. For proximal obstruction type IIand IV were preferred and for distal obstruction type III was chosen. However, type I could be applied in any situation. 4. Early complocation occurred in 9 cases(12.5%). Clinical improvement with decrease in bilirubin level was observed in 17 of 21 cases in which follow-up data was available over 2 months. 5. Through the experience with those 72 cases it is recommended that appropriate type of internal biliary drainage should be selected according to prognosis, obstruction level and clinical findings of each patient.