Malnutrition among children under age five is the major public health problem in the developing world
particularly in Ethiopia. The aim of this study was then to determine statistically the determinants of children malnutrition,
using 2011 DHS data. The overall prevalence of underweight among children in Ethiopia was 36.4%. Bayesian
Semi-parametric regression model was used to flexibly model the effects of selected socioeconomic, demographic, health and
environmental covariates. Inference was made using Bayesian approach with Markov chain Monte Carlo (MCMC)
techniques. It was found that the covariates sex of child, preceding birth interval, birth order of child, place of residence,
mother’s education level, toilet facility, number of household members, household economic status, cough, diarrhea and
fever were the most important determinants of children nutritional status in Ethiopia. The effect of child Age, mother’s age at
child birth, and mother’s body mass index were also explored non-parametrically as determinants of children nutritional
status. It is suggested that for reducing childhood malnutrition, due emphasis should be given in improving the knowledge
and practice of parents on appropriate young child feeding practice and frequent growth monitoring together with appropriate
and timely interventions.