The site of confluence of cystic duct (CD) and common bile duct (CBD) was surveyed by ERCP in 1100 cases. Abnormal confluence was found in 65 (5.9%). There were three types of variations: (1) Low-sited confluence in 54/65 (83%), in which the length of CBD was significantly shorter than that of common hepatic duct (CHD). (2) Very low-sited confluence in 9/65 (13.8%), in which CD joined CBD at the level of CBD sphincter (3) High-sited confluence in 2/65 (3.2%), in which CD joined right hepatic duct or the beginning of CHD. The clinical implications of these anatomical variations are discussed.