A simple morphometrical method was developed using a color image analyzing system, which allowed quantitative evaluation of parenchymal liver cell volume and total hepatocyte number in cirrhotic patients. With this method, we estimated these values in 29 cirrhotic patients who underwent hepatic resection (nine cases) or nonshunting operation (20 cases). Liver volume, calculated from computed tomographic images, was 976 ± 196 cm3 (range = 602 to 1,376 cm3); the parenchymal cell volume ratio, obtained based on liver histological appearance with silver stain, was 0.665 ± 0.092 (range = 0.510 to 0.881); and the parenchymal cell volume, calculated by multiplying the liver volume with the parenchymal cell volume ratio, was 645 ± 140 cm3 (range = 403 to 936 cm3). The total hepatocyte number obtained in a similar manner using hematoxylin-stained specimens was 1.72 ± 0.56 × 1011 (range = 0.74 to 2.94 × 1011). The validity and applicability of the method is discussed, and the data are compared with those reported in other studies.