A total of 72 cases of internal biliary drainage procedure has been done percutaneously at Departement ofRadilogy, Seoul Natinal Universtiy Hospital for recent 4 and half years since August 1981. Five different types ofinternal 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. Thenext was pancreas head carcinoma in 16 cases, followed by metastatic carcinoma and other disease. 2. Type Iinternal drainage, classical internal and external type with distal end in duodenum, was applied in 43 cases asthe most comon one. Type II, modification of type I with distal end in CBD, was applied in 17 cases. Type III,endoprosthesis distal end into duodenum, was applied in 7 cases. Type IV, endoprosthesis just across theobstruction in bile duct, was applied in 2 cases, Type V, combined type of any internal drainage with externaldrainage, was applied in 3 cases. 3. According to various obstruction level, prefered type could be selected. Forproximal obstruction type II and IV were preferred and for distal obstruction type III was chosen. However, type Icould be applied in any situation. 4. Early complication occurred in 9 cases(12.5%). Clinical imporvement withdecrease in bilirubin level was observed 17 of 21 cases in which follow-up data was available over 2 months. 5.Though the experience with those 72 cases it is recommended that appropriate type of internal biliary drainageshould be selected according to prognosis, obstruction level and clinical findings of each patient.