Background: According to World Health Organization (2013) approximately 35% of the under-fivemortalities are due to nutrition related factors & 4.4% of deaths are due to severe wasting. It has been found that Vitamin D levels are low in children with malnourished and very sick children. Even the prevalence of vitamin D deficiency is very high in Indian subcontinent. In WHO recommendations for the management of severe acute malnutrition there is no role of vitamin D supplementation. Objective: To study the effect of vitamin D supplementation on severe acute malnourished children admitted in nutritional rehabilitation Centre. Design: Single blinded Randomized controlled, parallel group trial. Setting: Nutritional Rehabilitation Centre (NRC) of a tertiary care hospital. Participants: 70 severe acute malnourished children aged 6 months to 59 months admitted in the NRC were randomized by computer generated random table. Intervention: 6 lakhs IU vitamin D was given intramuscularly on day one of therapy after an informed consent to the study group and other group was given only management of SAM. Main Outcome measure: outcome indicators of NRC i.e. cure rate, death rate, non-responders, relapse rate. Results: There was no significant difference in the outcome indicators of NRC i.e cured, death, non-response and relapse rate (p=0.32) and average weight gain (p= 0.38) and length of stay (p=0.42) between the two groups at discharge but wasting (p=0.02 on first, p=0.008 on third and p=0.04 on fourth follow ups respectively) improved significantly on follow ups. Conclusions: vitamin D supplementation does not have any significant improvement in the outcome indicators at discharge but significantly improves wasting on follow up.