Liver dysfunction involving toluene intoxicity includes elevation of transaminase level and delayed complications of liver failure, but its effect on hepatitis B virus (HBV) infection is as yet unknown. Here, we report a case of fulminant hepatitis B developed in a toluene abuser. A 23-year-old female toluene abuser was admitted to a local clinic because of nausea, vomiting, and dizziness, and a mild elevation of serum transaminase level was identified. She was treated as an outpatient, but continued toluene inhalation during follow-up. Five days later, she was found in a drowsy state of consciousness and taken to the emergency unit of our institution. Laboratory findings showed an alanine aminotransferase level of 4,659IU, a remarkably prolonged prothrombin time, and she was diagnosed with fulminant hepatitis B. Intensive care was carried out, but she died the next day. Molecular analysis revealed that the HBV isolate was classified as genotype C, and nucleotide positions that are prone to fulminant hepatitis were A at 1,762 and G at 1,764 in the core promoter region, and G at 1,896 in codon 28 in the precore region. The long-term toluene inhalation could have contributed to drastic clinical course of acute hepatitis B in this patient.