Aim and Objective: This study was conducted with the aim to estimate the prevalence of malnutrition and associated factors among children under 5 years of age in Frash Town Islamabad. Methodology: It was a cross sectional descriptive study. 400 children under 5 years were selected by using non probability convenient sampling. Analysis: Descriptive statistics was used to find the frequencies and percentages while inferential statistics was used to determine the association between nutritional status of under 5 children and different variables. Results: Out of 400 subjects, 21% had normal nutritional status 20% were at risk of malnutrition and 77% were found to be malnourished. Statistically significant relationship was found between nutritional status of under 5 children and socioeconomic status, parent’s education. Conclusion: Overall results showed that 77% of the children under 5 were malnourished. There is a need to plan composite interventions to elucidate the factors that place children at greater risk for malnutrition.