Malignant neoplasms are the second most common cause of infant mortality worldwide. Nutritional deficiency occurs in approximately 60 % of children with cancer and contributes to a decrease in immune function, delayed wound healing, impaired drug metabolism, and a severe and recurrent course of infectious complications. Malnutrition has a particularly adverse effect on outcomes and is one of the main preventable causes of death in infants. Given the growing trend in the incidence of cancer in children of the first years of life, the lack of standards and recommendations for the therapeutic nutrition of these patients, the organization of nutritional support for infants in the context of pediatric oncology is becoming increasingly important. Our article presents current trends in the assessment and correction of the nutritional status of infants with cancer.