SUMMARY In children with cancer, chemotherapy and radiotherapy of ceratin tumors of the head and neck, reduce the production of saliva causing dry mouth, mouth ulcers and mucositis. Dental problems of children with cancer are summarized in caries, dry mouth and tightening of the muscles of the face. Likewise, chemotherapy, radiation and the cancer itself, cause changes in taste of the child with cancer. All these circumstances are reflected in the low nutrient intake and future development of malnutrition for which it is necessary to be vigilant and to suggest preventive measures.