Background/AimsThe Ministry of Health and Welfare and the Korea Centers for Disease Control and Prevention in South Korea have been organizing hepatitis B virus (HBV) vertical infection prevention projects since July 2002. In this single-institute study, the results of surveys conducted in target mothers who delivered babies in a tertiary hospital were investigated and analyzed.MethodsOf the 9,281 mothers and their 9,824 neonates born between July 2002 and December 2012, 308 hepatitis B surface antigen (HBsAg)-positive mothers and their 319 neonates were selected for this study, and their records were analyzed retrospectively.ResultsA total of 308 mothers were HBsAg-positive, with an HBV prevalence of 3.32% (308/9,281). There were 319 neonates born to these HBsAg-positive mothers, and 252 were confirmed to as either HBsAg-positive or -negative. Four were confirmed as HBsAg-positive, with a 1.59% (4/252) HBV vertical infection rate. All the mothers of neonates who had an HBV vertical infection were hepatitis B e antigen (HBeAg)-positive. Among the HBsAg-positive neonates, three were HBeAg-positive and had an HBV DNA titer of 1.0 × 108 copies/mL.ConclusionsThe HBV prevalence of mothers was 3.32% (308/9,281), and their vertical infection rate was 1.59% (4/252). Thus, the South Korean HBV vertical infection prevention projects are effective, and, accordingly, HBV prevalence in South Korea is expected to decrease continuously.