Hepatitis B immunoglobulin (HBIG) is administered for the passive immunisation of all infants born to HBsAg-positive mothers within 12 h of birth. Adverse effects of HBIG are very rare. In this study, we report a newborn (a female, 33 weeks' gestation and 2030 g birth weight) developing anaphylaxis after HBIG administration. The mother was a Hepatitis B virus (HBV) carrier. Hypotension and erythematous rash developed 7 min after HBIG administration. Reporting the first anaphylaxis case in newborns due to HBIG in literature, we suggest the condition be taken into account, and requisite precautions should be taken against this probable complication in the newborn.