The traumatic pancreatic fistula was the one of the diseases to be hardly confirmed wi- thout operation. It had been usually suspected if the ascites contained the high level of amylase after abdominal trauma. After ERCP ivas developed and used in the diagnosis of the pancreatic diseases effectively it became fpossible to confirm the pacreatic fistula before- operation We have recently had the opportunity to experience one case of pancreatic fistula after trauma confirmed with ERCP. This 26 year old housewife was admitted due to severe upper abdominal pain for 4 hours, She allegedly fell 14 hours before admission, hitting her upper abdomen on a rock. On admission her abdomen was tender, especially in both upper quadr- ants with rebound tenderness. CBC shoived leukocytosis with shift to left. Diagnostic abdom- inal tap was performed and gross blood ivas drawn. With the impression .of splenic rupture exploratory laparotomy was done. At operation the spleen appeared to be normal and a pancreatic contusion over the mid-portion ivas noted with hematoma in the transverse meso- colon. Drainage procedure were done. On the first day after operation a severe abdominal pain was developed with running fever. The serum amylase was 705 units/L. Paracenthesis was done and 500cc. Of clear fluid vas aspirated on the next day. Total protein of ascites was 2.7gmg and amylase 1980 units. After two days the pain was subsided and ascites was drained well through the rubber drain inserted at previous operation. The patients condition had been in improving state untill the post op. 14th day when a sudden abdominal pain was developed again with incr- eased serum amylase(568 U./L). Upper G- [ study done at that time revealed a extragastric mass effect on the posterior wall of the stomach suggestive of pancreatic enlargement. Abdominal ultrasonography showed some questionable mass shadow at the site of right from midline and about 4cm above the umbilicus. The rubber drain was not functioning and an exploration with a Kelley clamp and drain was changed to rubber tube. After that the asc- ites was drained well and patient became comfortable. The amylase in ascites drained through t!ibe was 15000 v.nits. On the 22th day after operation ERCP was done using JF type B2 with 60p Hypaque as contrast media. The main pancreatic duct was visualized well from head to body. Bu', the main pancreatic duct ivas abrup?ly cut off and a fistulous tract was seen which suggested the pancreatic internal fistula. The patient was treated with conservative methods for two weeks with some improvernent. On the 39th day after operation the second operation for partial pancreatectomy was done because of recurrent pancreatitis.