Neonatal tetanus persists as a public health problem in many developing countries including Ethiopia. Maternal tetanus toxoid vaccination is a cornerstone to prevent neonatal tetanus. However, its prevalence is low in Ethiopia, and little has been devoted to its spatial epidemiology and associated factors. Hence, this study aimed to explore the spatial pattern and factors affecting tetanus-unprotected births in Ethiopia. A further analysis of the 2016 Ethiopia Demographic and Health Survey data was conducted, and a weighted sample of 7590 women was used for analysis. Spatial analysis was done using ArcGIS and SaTScan software. A binary logistic regression model was fitted to identify factors and variables with a p-value <.05 were considered as statistically significant. About 54.13% (95% CI: 53.01, 55.25) of births were not protected against neonatal tetanus, and spatial clustering of tetanus unprotected births was observed (Moran's I = 0.144, p-value = .028). The primary and secondary SaTScan clusters were detected in Northeastern Tigray, Eastern Amhara, and almost the entire Afar (RR = 1.34 & LLR = 66.5, p < .01), and in the Somali region, and the western border of Gambela (RR = 1.44 & LLR = 31.3, p < .01), respectively. Tetanus unprotected births were higher among women without formal education (AOR = 1.63; 95% CI: 1.29, 2.04), came from poor households (AOR = 1.27; 95% CI: 1.12, 1.45), who had no ANC contact (AOR = 6.97; 95% CI: 6.21, 7.88), and who were not exposed to the media (AOR = 1.26; 95% CI: 1.09, 1.47). Hence, tetanus-unprotected birth hotspots require priority interventions, and it is good if the targeted interventions consider the identified factors.