Pancreatic ascites is massive and chronic retention of ascites caused by benign pancreatic diseases. It is thought that in many cases this disease is caused by a formation of internal pancreatic fistula associated with chronic pancreatitis. This time we experienced a case of pancreatic ascites with alcoholic chronic pancreatitis. A 62-year-old man was found having massive ascites with high amylase and high protein. Endoscopic retrograde cholangiopancreatography (ERCP) revealed a portion which appeared to be pseudocyst and following abdominal CT showed intraabdominal leakage of a contrast medium. So the patient was diagnosed as pancreatic ascites. Conservative treatments including high caloric infusion therapy and centesis of ascites were ineffective. Frey's operation was carried out, with a successful outcome.