Malnutrition increases post surgical morbimortality, hospital stance and economical costs. Possibilities of nutritional intervention in surgical patients are important. Early enteral nutrition is better than total parenteral nutrition in patients under surgery. Periroperaoty nutritional support must be administrated to patients with severe or middle undernutrition and will be under surgery, during 7-14 days before surgical intervention, if this intervention could be delayed. Total parenteral nutrition will be not used regularly in patients under mayor digestive surgical procedures. Inmunonutrition has been demonstrated useful in surgical patients. Evidence demonstrates that inmunotritional formulas decrease incidence of infections, hospital stance and time of ventilation in patients in UCI wards. New research areas have been explored in this topic area, carbohydrate utility in presurgical patients and probiotic in enteral formulas.