Abstract: Mother to child transmission of hepatitis B is now been recognized as a major route of acquisition of hepatitis B infection. This study thus aimed to evaluate the rate of vertical transmission of hepatitis B in a cohort of mothers and their children in Abuja, Nigeria. This study was carried out between May to September 2011 in Abuja, Nigeria. In this cross-sectional study, the prevalence of sero-markers to carrier status of hepatitis B (HBsAg) and disease progression and capacity for infectivity (HBeAg) in paired sera samples of apparently healthy mothers and their children in sub-urban communities of Lugbe and Gwagwalada, federal capital territory, Abuja, Nigeria was investigated. Informed consent was received from parents (Mothers and fathers) to include their children. Only children between 6 months to 3.5 years were included the study. Only subjects positive for HBsAg were screened further for HBeAg. A total of 250 mothers and their 291 children were the study subjects. Overall prevalence of HBsAg in the mothers and children studied were 33 (13.2%) and 20 (6.9%). About 9 (27.7%) mothers who were positive for HBsAg were seropositive for HBeAg. A total of 7 (35.0%) children out of 20 HBsAg seropositive children were positive for HBeAg. The risk of vertical transmission of hepatitis B from mothers to their children was high; 7 (77.7) children out of 9 HBeAg positive mothers were HBeAg positive. All 7 HBeAg positive children were children of HBeAg seropositive mothers making a total percentage of perinatally transmitted hepatitis B to be 77.7%. The risk of vertical transmission of hepatitis B was high. Screening for hepatitis B in pregnant women should be a routine practice in the antenatal clinics so as to institute an early immunization for at risk infants after birth.