Ganoderic acid, from Ganoderma lucidum, at 8 mu g/ml inhibited replication of hepatitis B virus (HBV) in HepG2215 cells over 8 days. Production of HBV surface antigen and HBV e antigen were 20 and 44% of controls without ganoderic acid. Male KM mice were significantly protected from liver injury, induced with carbon tetrachloride, by treatment with ganoderic acid at 10 mg and 30 mg/kg center dot d (by intravenous injection) 7 days. Ganoderic acid at the same dosage also significantly protected the mice from liver injury induced by M. bovis BCG plus lipopolysaccharide (from Escherichia coli 0127:B8).