Liver biopsy specimens from 95 patients with chronic active hepatitis type B were studied to define the incidence of portal tract and/or septal neutrophilic infiltration and its relationship with other morphohistologic factors and with liver function tests. Neutrophils were identified in the portal tracts and fibrous septa in 59 cases (62%), among which 19 cases (20%) showed four or more neutrophils per high-power field. Significant neutrophilic infiltration (greater than 6 per high-power field) was observed in only seven (7.4%) of 95 cases. Multiple-regression analysis revealed that neutrophilic infiltration was significantly associated with marginal duct proliferation, bile duct proliferation, and an elevated alanine aminotransferase level. Applying a partial correlation coefficient, it was shown that neutrophilic infiltration was not related to piecemeal necrosis after controlling for marginal duct proliferation or bile duct proliferation. The findings suggest that in chronic active hepatitis B, while piecemeal necrosis interferes with bile flow at the limiting plate region, marginal duct and bile duct proliferations follow and lead to the accumulation of neutrophils.