In the cirrhotic and precirrhotic liver, there may be small foci with increased cellularity and amphophilic cytoplasm. These are microscopic lesions that do not form macroscopically detectable nodules, which differ from the macroscopically apparent nodules of dysplastic nodules. In the present study, we assessed the proliferating activity of 12 hyperplastic foci in 11 patients with cirrhosis or chronic hepatitis, by staining for agyrophilic nucleolar organizing regions (AgNOR). The mean AgNOR count per nucleus in the hyperplastic foci ranged from 0.96 to 1.36 (mean, 1.13; SD 0.12), and from 0.81 to 1.06 (mean, 0.94; SD 0.08) in the controls. The AgNOR count in the hyperplastic foci was significantly higher than that in the controls (P < 0.01). Small hyperplastic foci show increased proliferative activity. Further study on these foci is required to clarify their relation to hepatocarcinogenesis.