The prevalence of hepatitis B virus (HBV) is particularly high in Asian countries, including Taiwan. Previous studies have reported detection of HBV surface antigens in tears and aqueous humor of HBV-seropositive individuals, suggesting that ophthalmologists may be at risk of contracting HBV infection by treatment of such patients. Herein we report the case of an asymptomatic Taiwanese HBV patient in whom HBV was detected in aqueous humor using PCR. To our knowledge this is the first report of HBV detection in aqueous humor by PCR. Eye care providers should take all necessary precautions when treating individuals who have or are at high risk of being infected with HBV.