Nutrition is an integral component in the management of patients with cancer. A nutrition screening is essential to identify risk of malnutrition. Screening is followed by a nutrition assessment, which is the first step of the nutritional care process, and is used to make a nutrition diagnosis, determine appropriate intervention, and monitor and evaluate nutritional care outcomes. Nutritional management of the patient with cancer includes oral dietary therapy, enteral nutrition, and parenteral nutrition. The concurrent use of supplements, especially highdose antioxidants or complex botanical agents, during chemotherapy or radiation therapy can be problematic due to drug supplement interaction. Symptoms that interfere with eating include anorexia, nausea, vomiting, diarrhea, constipation, mouth sores, trouble with swallowing, and pain. Poor nutritional status can result in a decreased quality of life, functional status, and response to therapy. Nutrition screening and assessment of cancer patients can identify those at risk for malnutrition.