Listeria monocytogenes is one of the important causes of neonatal sepsis and listerial neonatal infection manifests in two forms : Early-onset sepsis syndrome, associated with spontaneous abortion, still birth, preterm labor, granulomatosis infantiseptica, respiratory distress, sepsis, hemodynamic compromise and late-onset listerosis mainly associated with meningitis. Cases of neonatal listerosis reported in Korea have been rare and all were full term newborns. We, herein, report a case of early-onset sepsis due to L. monocytogenes in a extremely low birth weight infant who were born in a critical condition and succumbed in the second day of life despite the intensive care.