Abstract:Objective ：To elucidate the clinical significance of detecting amylase level of bile during ERCP. Methods ：Bile samples for amylase measurement were taken from selected patients who underwent ERCP. According to their radiological and clinical manifestations, these patients were divided into abnormal junction of pancreatic and bile ducts(AJPB), short common channel(SCC) and long common channel(LCC) groups. Results ：The amylase level of bile of AJPB group was significantly higher than that of SCC and LCC groups, and the amylase level of bile of LCC group was much higher than that of SCC group. Furthermore, in AJPB group, the amylase level of bile was significantly higher than serum level. Conclusions ：Amylase level of bile is partly dependent on the length of pancreaticobiliary common channel, and a longer common channel usually is accompanied with a higher amylase level of bile. An unusually high amylase level of bile is a reliable evidence for diagnosing pancreaticobiliaryreflux, and measuring amylase content of bile provides an important and adjunctive tool for diagnosing pancreaticobiliary maljunction, especially for those with a common channel shorter than 15 mm, and these patients should be treated as AJPB.