This study compares the histology of liver biopsies in precore mutant (PCM) and wild-type hepatitis B virus (HBV) infection. Thirty cases of PCM and 60 cases of wild-type HBV infection were included. Patients were diagnosed on the basis of serological profile and HBV DNA assessment. Liver biopsies in each case were assessed for histological activity and stage of fibrosis using a modification of Knodell's scoring system. There was no statistically significant (P=0.14) difference in histological activity in the two groups. The difference in stage of fibrosis in the two groups was statistically significant (P=0.001). Quantitative estimation of viral load did not show any correlation with liver histology. PCM HBV showed greater stage of fibrosis compared with wild-type infection, and this may be related to disease progression and lack of response to therapy.