Malnutrition with its different type, still prevalent worldwide leading to 2.2 million deaths in children of less than five years of age. The severity of acute malnutrition usually increase the risk for death from dehydration, infections due to the immunity depression. Severe acute malnutrition is considered severe and acute when short history of the illness with short period of food deprivation and subsequently development of illness and mortality and it will be complicated by metabolic disturbances and loss of appetite. The objective of this study is to determine prevalence of malnutrition among Sudanese children and its precipitating factors. This was prospective, observational, descriptive, cross sectional, hospital based study where 767 children with malnutrition out of 8000 patients reported to the emergency room were enrolled in this study, aged between 6-60 month, during the period between June 2011-May 2011, in Gafar Children Hospital (GCH), Khartoum. Detailed history local and general examination, interview with care givers through pre-tested questionnaire. Marasmus is dominant among those who were under the age of two tears 429 (57.1%) patients and across all ages 491(65.4%) patients. The prevalence was 9.4%. Most of the patients were male 404(53.8%) patients, with low socio-economic status 537(71.5%) patients, 537(82.8%) Lack breast feeding in first year and early weaning .low socio-economic status were the precipitating factors for malnutrition. Dehydration was the most common presentation to the hospital and septicemia is the usual cause of deaths. Case fatality rate 49(6.5%) due to septicemia 27(55.1%) patients. This study showed marasmus were the common type of malnutrition across all ages in general and in those who were less than two years in particular. The prevalence was 9.4%. Male sex, low socio-economic status, Lack breast feeding in first year or early weaned with less than six month were the risk factors for malnutrition. Dehydration was the most common presentation to the hospital, septicemia was the usual cause of death and case fatality rate was 6.5%)