Immunization remains one of the most successful and cost-effective public health interventions worldwide. The purpose of this study was to examine the individual and socioeconomic factors that influence childhood immunization coverage in Nigeria. The health belief model and the social ecological model were used as the theoretical framework for the study, which examined the effects of individual, parental, and socioeconomic factors on complete immunization among Nigerian children. Univariate, bivariate, and multivariate tests were conducted within a secondary analysis of 2013 Nigerian National Demographic and Health Survey was done. Of 27,571 children aged 0 to 59 months, 22.1% had full vaccination and 29% never received any vaccination. Immunization coverage was significantly related to the socioeconomic status of the child's parents, region, and marital status (p