Infant mortality continues to remain one of the priority public health issues in developing countries like Nepal. Despite achievements in other public health sectors, the infant mortality rate (IMR) has only minimally or no changes (48 deaths per 1000 live births in 2006 to 46 deaths per 1000 live births in 2011), leaving a resultant proportion that is still exceptionally high compared to other Asian countries. It is imperative to identify and compare contributing factors that are significantly responsible for infant deaths to provide evidence-based recommendations for improving infant's health promotion and planning for the country. However, comprehensive analyses that use nationally representative data to identify and compare key factors associated with infant mortality are limited in Nepal, and, therefore, this study aimed to fill the gap. This study has identified and compared the key factors of infant mortality in Nepal. Hence, this research will be useful to all the academicians and researchers who are looking forward to the evidence-based study for the factors associated with infant mortality in developing countries.