Cachexia is a frequent syndrome in patients suffering from advanced cancer; it is characterized by anorexia, weight loss, and malnutrition, which combined with other psychic and social consequences lead to a deterioration in a patient's quality of life. Various factors play a role in the development of cachexia; these depend on the patient, the type of tumor, and the treatments received. Its complexity warrant the intervention of an interdisciplinary team, in which nursing plays an essential role. Up to present time, the results of pharmaceutical treatment have been rather unfavorable; therefore, nutritional treatments based on advise for concrete problems and dietary supplements gain importance; enteral or parenteral nutrition are reserved for selected cases. Other important aspects are psychological support, control of associated symptoms and the prevention and treatment of any complication which may appear.