The following conclusions were made on the basis of studies on endoscopic retrograde cholangiograms of 94 cases among which diseases originated from the pancreas and biliary tract were excluded. 1) Intrahepatic bile ducts were satisfactorily visualized by supine and prone position with the head down. The normal intrahepatic bile ducts showed tapering-off smoothly. Conflux of the intrahepatic bile ducts were divided into seven types. 2) The common hepatic duct and bile duct measured 4 to 9 mm in the maximum diameter. The extrahepatic bile ducts tended to be dilated in diameter with aging. 3) The Vaterian bile duct was within 10 to 20 mm in the length and the papilla-orifice 1 to 1.5 mm in diameter. With the normal cholangiogram, the Vaterian bile duct was slightly irregular in the contour. The Vaterian segment showed contraction and relaxation rhythmically; one cycle of the movement averaged 11 to 15 seconds. A common channel was observed in 73 % of 94 cases. It was difficult to observe "the ampulla of Vater" on X-ray photographs. 4) The cholecystogram looked like a pear with smooth contour, showing various changes in shape according to position of patients. The cystic duct, in most cases, connects with the extrahepatic bile duct at the mid-portion. The cystic duct was the longer in length the shorter became the choledochus. 5) As for endoscopic findings, the major papilla appeared smooth on surface and slightly red in color. According to the shape, the major papilla can be classified as hemispherical, hemielliptical and flat types and, less frequently, peculiar type having a separate orifice.