BackgroundImmunization remains one of the most important public health interventions to reduce child morbidity and mortality. The 2011 national demographic and health survey (DHS) indicated low full immunization coverage among children aged 12–23 months in Ethiopia. Factors contributing to the low coverage of immunization have been poorly understood. The aim of this study was to identify factors associated with full immunization coverage among children aged 12–23 months in Ethiopia.MethodsThis study used the 2011 Ethiopian demographic and health survey data. The survey was cross sectional by design and used a multistage cluster sampling procedure. A total of 1,927 mothers with children of 12–23 months of age were extracted from the children’s dataset. Mothers’ self-reported data and observations of vaccination cards were used to determine vaccine coverage. An adjusted odds ratio (AOR) with 95 % confidence intervals (CI) was used to outline the independent predictors.ResultsThe prevalence of fully immunized children was 24.3 %. Specific vaccination coverage for three doses of DPT, three doses of polio, measles and BCG were 36.5 %, 44.3 %, 55.7 % and 66.3 %, respectively. The multivariable analysis showed that sources of information from vaccination card [AOR 95 % CI; 7.7 (5.95-10.06)], received postnatal check-up within two months after birth [AOR 95 % CI; 1.8 (1.28-2.56)], women’s awareness of community conversation program [AOR 95 % CI; 1.9 (1.44-2.49)] and women in the rich wealth index [AOR 95 % CI; 1.4 (1.06-1.94)] were the predictors of full immunization coverage. Women from Afar [AOR 95 % CI; 0.07 (0.01-0.68)], Amhara [AOR 95 % CI; 0.33 (0.13-0.81)], Oromiya [AOR 95 % CI; 0.15 (0.06-0.37)], Somali [AOR 95 % CI; 0.15 (0.04-0.55)] and Southern Nation and Nationalities People administrative regions [AOR 95 % CI; 0.35 (0.14-0.87)] were less likely to fully vaccinate their children.ConclusionThe overall full immunization coverage in Ethiopia was considerably low as compared to the national target set (66 %). Health service use and access to information on maternal and child health were found to predict full immunization coverage. Appropriate strategies should be devised to enhance health information and accessibility for full immunization coverage by addressing the variations among regions.