Background: Nigeria ranks as one of the countries in the world with a considerable burden of neonatal mortality. This study aims to investigate the association of socioeconomic, bio-demographic and health/behavioural factors with neonatal mortality in the country using the most current available evidence. Methods: The 2013 Nigeria demographic and health survey (NDHS) dataset was analyzed. Multiple logistic regression analysis was applied to identify determinants associated with neonatal mortality. The role of breastfeeding was examined by conducting analyses with and without adjustment for „breastfeeding status?. Complex samples analysis was used to control for the complex sampling design used in NDHS. Results: Neonatal mortality rate (NMR) stood at 33 deaths per 1000 live births. With or without adjustment for„breastfeeding status?, bio-demographic factors – maternal marital status, rural-urban residence, birth size, gender of child, birth interval and maternal body mass index (BMI) – were predictive of neonatal mortality. Maternal age and ethnicity became additional bio-demographic predictors after adjusting for „breastfeeding status?. Maternal literacy (socioeconomic factor) and mode of delivery (health/behavioral factor) were significant predictors only when breastfeeding status was not adjusted for. Conclusions: Bio-demographic factors formed the bulk of predictors of neonatal mortality in Nigeria. The effect of socioeconomic and health/behavioural factors disappeared when breastfeeding status was adjusted for. Intervention programs would need to prioritize the identified predictors for an accelerated reduction of neonatal mortality in Nigeria. Keywords: Neonatal mortality, Nigeria, Socioeconomic, Bio-demographic, Health/behavioral determinants