More than one-fourth of under five children (about 150 million) are underweight while about onethird (182 million) are stunted. Geographically more than 70% of protein energy malnutrition children live in Asia, 26% in Africa and 4% in Latin America and the Caribbean2. Malnutrition among children is a public health problem in Nepal. Nepal Demography and Health Survey (NDHS, 2011) reported that 29 % children are underweight, 41% stunted and 11% wasted. Material and Methods: A base-line data were analyzed and prepared this article with objective was prevalence and its associated factors of stunting, underweight and wasting among children less than 3 years old from the study that was conducted a pre-post with controlled design conducted in Mahottari district of Nepal in 2012. Results: In this study, Prevalence of wasting, stunting and underweight was 31.1%, 42.3% and 45% of children less than 3 years respectively. The study found that the prevalence of severe wasted and wasted were 18.2 % and 12.9 % respectively, while the prevalence of stunting and severe stunting status of children were 20.7% and 21.7% and the prevalence of underweight and severely underweight children were 20.2% and 24.9%. Conclusions: Present study shows that the prevalence of malnutrition (underweight, stunting, and wasting) is still major health problems among children less than 3 years, particularly in the Central Terai region.