Hospital malnutrition remains a widespread problem throughout European hospitals, affecting 20–40% of adult and pediatric patients. In combination with an underlying disease, malnutrition impairs immune and muscle function, prolongs wound healing, initiates intestinal dysfunction, and therefore, increases the risks of serious complications and reduces quality of life. Ideally the role of nutritional support is to prevent undernutrition and, if it is already present, to restore normal nutritional status, while avoiding nutritional complications, and to promote developmentally adequate feeding habits and skills. This article aims to discuss how to achieve this in pediatric patients and describe the eligible methods of nutritional treatment. The choice of treatment method depends on the underlying disease, age of the patient, gastrointestinal status, possibilities of oral intake, and costs and family feeding habits. With regard to all these factors, and particularly the individual nutritional needs and current nutritional status, the intensity of nutritional support should increase in a stepwise manner from intensified dietetic counseling, over various modalities of enteral feeding to parenteral nutrition. As a general recommendation, when the clinical condition precludes oral intake, enteral nutrition should be used whenever there is a functional gastrointestinal tract. Parenteral nutrition is reserved for children with inexistent, inaccessible or dysfunctional gut, and under these clinical conditions it is a lifesaving procedure. Regardless of the modality of nutritional support, in severely malnourished children, particular care should be taken to avoid the development of the refeeding syndrome. The goals of nutritional management are best achieved, and with an optimal cost-benefit ratio, through the establishment of a nutrition support team, consisting of a pediatrician with an expertise in clinical nutrition, a nurse, a dietician/nutritionist and, if possible, a pharmacist.