Background: Vaccine preventable diseases (VPDs) account for 17% of the global under-five mortality per annum and more than half of these deaths have occurred in sub-Saharan Africa. Ethiopia is one of the ten countries which account for about 62% of unprotected children and one of the three countries (Ethiopia, Nigeria, and the Democratic Republic of Congo) in which half of the world’s child deaths have occurred are in sub-Saharan Africa. The main objective of this study is to understand the current status of complete immunization coverage and examine its determinant factors among children in Ethiopia.Method: Bayesian multilevel logistic regression models have been utilized to realize the objectives of the research. The dataset used for this study comes from the 2016 Ethiopian Demographic and Health Survey (EDHS). The convergences of parameters are checked by using Markov chain Monte-Carlo (MCMC) using SPSS and MLwiN software. Results: The descriptive result revealed that, out of the 1929 children who are supposed to complete all basic childhood vaccines, 699 (36.2%) children were completely vaccinated, while 1230 (63.8%) children were incompletely vaccinated. Moreover, regions Afar, Somali and Gambela have the least proportion of vaccination coverage. Among the multilevel models, Bayesian random coefficient model is found to be a better model to estimate the vaccination coverage of children. Using this model, it has been found that factors like place of residence, maternal educational, mother occupation type, Antenatal Care (ANC) utilization, Postnatal Care (PNC) utilization, type of pregnancy, household wealth index, and field worker visit were found to be the significant factors that influences the vaccination coverage. Conclusion: In general, it has been estimated that the vaccination coverage in the country is relatively low and there was significant variation in the level of vaccination coverage in regions of the country.