Background: Fertility is one of the elements in population dynamics that has significant contribution towards changing population size and structure over time in the world. This study investigates determinant factors of fertility among women in Ethiopia. Methodology: The data used for the analysis was obtained from the 2016 Ethiopia Demographic and Health Survey which was implemented by the Central Statistical Agency. The survey collected a total of 15,683 successfully interviewed women aged from 15-49 years out of this 9,602 women were considered in this study. Multilevel Negative binomial analysis was selected to investigate the effect of socioeconomic, demographic, environmental and health related factors on the number of children ever born per woman in Ethiopia. Results: Likelihood ratio test suggested that, the number of ever born children varies across regions and multilevel count regression model was better fit than the single level count regression model. The expected number of total children ever born for using Contraceptive use were lower than 0.9557 times as compared non-using Contraceptive mothers. The expected number of ever born child of farther who has job attachment is higher than 1.05 times that of father who has job attachment. Conclusion: based on the result we can conclude that wealth index, year of education and age of mother at first sex, contraceptive use are negatively associated with total number of ever born children. However, family size, age of mother, age of mother at first birth, number of living child’s, father’s occupation, region, ideal number of children and number of visits are positively associated with a total number of ever born children were as significant factors. Therefore, the government and other stakeholders should pay attention to the subject and develop intervention to improve on the significant factors identified on the current paper.