Extrahepatic obstructive jaundice refers to that form of jaundice arising from interfercnce with biliary ontflow caused by an obstruction somewhere along the course of the extrahepatic biliary tract. Because the obstruction so often requires surgical correction, this type of jaundice is also commonly called surgical jaundice. There are many diseases that produce obstuctivs jaundice but of all the causes for obstructive jaundice, gall stone and tumors are ',the most common, being responsible generlly for abont 75% of the cases. This study was carried out in 104 patients of obstructive jaundice confirmed by operation. They are 13cases of cholelithiasis 38 cases of choledocholithiasis, g cases of gall bladder cancer,25 cases of bile duct cancer and 19 caces of pancreatic head cancer. The cases studied involved the patients who were admitted to the departnant of internal medcicne and tranefe- rred to the department of general surery for operation in Seonl National University I-Iospital during the period from Jan. 1973 to Dec. 1979. The results obtained are summarized as follows; l. In causative diseaes the ratio of male to female was 3: 2 and the age ranged from 1g years old to 78 years old. The highest was 35 cases in gth decade and the next was 27 cases in 7th decade. 2. Biliary colic and dyspepsia were main chief complaints on admission in the casc of obstructive jaundice by stone disease and jaundice, weight loss, abdominsal pain were main chief complaints in the case of obstructive jaundice by malignant tumor. 3. The gall bladder was palpable in 3. 97o of obstructive jaundice by stone disease and in 45. 3 /p of obstuctive jaundice by malignant tumor. 4. The serum total bilirubin level was below 10mg/1ppml in the majority case of obstructive jaundice by stone disease (66. 7%) and above lSmg/100ml about half case of obstructive jaundice by malignant tumor (5p. G%) And in the case of obstructive jaundice by cholelithiasis, the serum total bilirubin level was above 7mg/1ppml in 23. 1%, but in the case of obstructive jaundice by choledocholithiasis the serum total bilirubin level was above 7mg/1ppml in 47. 4?:. 5. The serum alkaline phosphatase level elevated in all causative disease group but there was no significant difference among them. 6. There was no significant difference in serum transaminase level in each causative discase and in the majority case it ranged from 41 to 200 Karmen unit. 7. In urinalysis the frequenc of detection of urine sugar was particularlyh bigh in the ca."e of obstuctive jaundice by pancreatic head cancer compare to obstructive jaundice by other disease. 8. In the case of obstuctive jaundice by bile duct cancer, there was the highest detection rate of stool occult blood g. We could find the causes of biliary tract obstruction directy by radiologic examination in 65 caseas of 104 cases 10. There were 14 cases (13. 5zo) of wrong transfer diagnosis in department of internal medicine when the patients were transferred to department of generai surgery.