Background: Hepatitis B Virus Infection (HBV) and Gestational Diabetes (GDM) are two major public health problems in Nigeria. There is evidence to suggest a relationship between glucose intolerance and HBV. The insulin resistance state of pregnancy supports a predisposition to developing gestational diabetes in HBV positive pregnant women. The influence of HBV as an independent risk factor for developing glucose intolerance/GDM has not been well characterized in our region. This study investigated the impact of maternal HBV infection on glucose derangements in pregnant Nigerian women. Objective: To determine the effect of HBV infection on the development of glucose intolerance/Gestational Diabetes Mellitus in pregnant Nigerian women. Study Design:This was a comparative cross sectional study Setting: This study was concluded at the Obstetrics and Gynaecology Department, of State Hospital Abeokuta, South West Nigeria. Methods: Consecutive consenting pregnant HBV positive and HBV negative pregnant women without the usual risk factors were recruited for the study. A proforma was used to obtain sociodemographic information. The patients were screened for gestational diabetes mellitus with 75g oral glucose tolerance test (75g OGTT) at 24 – 28 weeks gestation.