Heterogeneous groups of hepatocytes with different staining characteristics to eosin are found in patients with various chronic liver diseases. These staining characteristics seem to have some relationship to the progression of chronic liver diseases. To examine this relationship, biopsy specimen from 184 liver disease cases, were examined by routine methods, histochemical methods for enzyme quantitaion. RNA staining and immunohistochemical, identification of albumin. The results were as follows. 1) Eosin-intense hepatocytes occupying part of the liver lobule or forming a whole nodule had a high incidence of binucleated cells; normal or elevated levels of glucose 6-phosphatase, succinate dehydrogenase and glutamic-oxaloacetic transaminase; increased nucleolar and cytoplasmic RNA; many albumin containing hepatocytes; and normal glucose 6-phosphate dehydrogenase activity. These eosin-intense hepatocytes seemed to be normal except for the intense staining of eosin and these hepatocytes were probably at the stage of regeneration. Pale hepatocytes with a weak affinity for eosin showed reduced function and to be dedifferentiated. Nodules containing these plale hepatocytes were more expansive. 2) Hepatocytes with different staining characteristics for eosin were found only in patients with chronic hepatitis with sublobular necrosis and liver cirrhosis. The eosin stained group was most frequently observed in the early stage of liver cirrhosis and disappered at late stages. Eosin staining was weak in hepatocytes with progressively increased, well developed cirrhosis with expansive regenerating nodules. 3) Correlations were present in a large number of cases between the size of the hepatic necrosis and the incidence of eosin-intense hepatocytes. This relationship was most prominent at the stage of resorbtion after hepatic necrosis. 4) In at least some specimens, eosin-intense hepatocytes were found around the portal vein. An adequate blood supply may thus be important factor for eosin intense staining.