Malnutrition is an important and common problem among hospitalized patients. Malnutrition increases patients morbidity and mortlity due to tissue damage and organ dysfunction, also it leads to long hospital stay. One of the most popular issues recently, nutritional support is considered as not only a supportive measure of therapy but also a major component of treatment. Nutritional support programs which applied by well organized and specialized teams significantly decreases complication rates. Administration of nutritional support is a dynamic process. This program should be regularly overwieved on the light of the latest clinical variables such as patient's physical activity, development of new complication, body temperature changes and infection.