The objective of this study is to assess the nutritional status of hospitalized patients and its effect on morbidity, mortality and length of hospital stay. Prospectively, 177 adult patients, admitted to units of Internal Medicine Department and ICU of Kasr Al-Aini Hospitals during the period from October, 2006 to March, 2007 were evaluated using the Subjective Global Assessment (SGA) questionnaire. Patients were followed to determine length of hospital stay, complications and in-hospital mortality. The sample consisted of 100 men and 77 women. The mean age was 50.01±10.37 years, with 29.9% over 60 years. Overall 87.6% were admitted to general wards and 12.4% were admitted to the ICU. According to the SGA, 41.8% of patients had moderate malnutrition or were at-risk of malnutrition and there were no severely malnourished patients. Men had increased risk of being malnourished compared with women (p= 0.002). A tendency to malnutrition was observed in older individuals, especially those 60 years and older (p<0.001). Complications were significantly more frequent among those at-risk of malnutrition (group B) as there was 32.2% of patients versus 20.3% of complication in patients of group A that were normonourished (p< 0.001 and, Relative Risk RR=2.20). Overall mortality was 15.3%of which 11.3% belonged to group B and only 4.0% were of group A (p=0.04). The average length of hospital stay was higher for the malnourished group, 25±14 days versus 14 days±8 days in group A (with p< 0.001). The study concluded thatMalnutrition is frequent in hospitalized patients at Internal Medicine Department on admission, and is a risk factor for morbidity, mortality, and prolongs the length of hospitalization. Efforts should be made to quickly assess the nutritional status of these patients with early initiation of nutritional interventions.