In the previous report (Part I), it was shown that the exocrine pancreatic function decreases significantly with aging. The present paper is concerned with studies on morphological changes of the pancreatic duct as evaluated by endoscopic retrograde cholangiopancreatography (ERCP). Among 2500 patients on whom ERCP had been performed, 100 were selected who showed no abnormalities in serum amylase, urine amylase and pancreozymin-secretin test (PS test). The patients were subdivided into three groups according to age in order to elucidate the morphological changes on the pancreatograms with aging: younger than 40 years of age; 41 to 60 years of age; older than 60 years of age. The length and diameter of the main pancreatic duct, diameter of the accessory pancreatic duct (Santorini), and the presence or absence of tortuosity and irregularity in the margin of the pancreatic duct. The following conclusions were made: (1) The length of the main pancreatic duct was 16.4+2.2cm (mean+S.D.), and no significant difference was observed among each age group or between males and females. (2) The main pancreatic duct had the largest diameter in the head, gradually tapering off in the body and tail of the pancreas. The diameter of the main pancreatic duct showed a significant increase with aging. (3) Irregularity of the margin and tortuosity of the main pancreatic duct and branches were observed in a significantly increased frequency with aging. These abnormalities, however, were mild. (4) The accessory duct was observed in 28 % of cases; the mean length was 2.5cm, the mean diameter was 1.3mm. (5) In considetation of the morphological changes on pancreatograms with aging, physiological ranges in the diameter of the main pancreatic duct were determined.