Introduction:The treatment used in neoplasias, chemotherapy and radiotherapy, generate a series of side effects that undermine the prognosis of cancer patients. Aiming mainly at nutritional status and mucosal integrity, we found the need for prevention in cases of patients who present with mucositis during anti-neoplastic treatment. Objective: To carry out a systematic review of the available knowledge about glutamine supplementation in the treatment of mucositis in patients undergoing antineoplastic treatment. Method: This is a literature review, selecting articles published between 2013 and 2015, in the Medline and Lilacs databases through Pubmed, with the following descriptors: glutamine and radiotherapy, glutamine and cancer and mucositis. Results: Studies indicate that the tumors that most affect the nutritional status of patients are head and neck neoplasms, esophagus, digestive tract and lung. Considering that the side effects of antineoplastic agents, such as vomiting, nausea, diarrhea, xerostomia, increased basal metabolic rate and mucositis, trigger a decrease in food intake, Leading the patient to malnutrition and cachexia. Mucositis is a result of inflammation of the oral mucosa or gastrointestinal tract. Several studies have evaluated the use of glutamine supplementation during antineoplastic treatment, since it depletes it over time, being related to cachexia, loss of muscle mass and, consequently, muscle glutamine, with substrate reduction for rapidly replicating cells, and may therefore be related to aggravation of oral mucositis and gastrointestinal tract. Conclusion: The use of glutamine in cancer treatment may be a viable option, especially in relation to the prevention of more severe degrees of mucositis. It is necessary the participation of a multidisciplinary team for the early identification of the alteration of the oral mucosa for a better treatment.