Thirty patients with chronic hepatitis (CH), 84 with liver cirrhosis (LC) and 42 controls, underwent noninvasive measurement of hepatic artery resistance index (RI) by means of Doppler ultrasound (US), at the porta hepatis and in the intrahepatic branches, in order to investigate possible changes related to: (a) the liver disease; (b) the site of measurement; and (c) ageing. The intrahepatic RI differed among LC, CH and controls (0.731, 0.690 and 0.643, p < 0.05), whereas the RI at the porta hepatis did not (0.754, 0.748 and 0.729, respectively). Intrahepatic RI correlated with age in LC (r = 0.51, p < 0.0001) and in controls (r = 0.49, p < 0.001). In LC, it correlated also with the presence and size of esophageal varices (r = 0.32, p < 0.05). In conclusion, an increase of hepatic artery RI in chronic liver diseases can be demonstrated when assessed in the intraparenchymal branches. The increase of hepatic artery RI with ageing should be considered in future studies.