Annotation.In Europe, the overall prevalence of iron deficiency anemia is 2-4%, with two peaks: young children (2.3-15%) and adolescents (3.5-13% – in boys, 11-33% – in girls). Iron deficiency occurs earlier than anemia, which is characterized by a decrease in the size and iron saturation of erythrocytes, and they become microcytic and hypochromic. Therefore, anemia can be prevented by early diagnosis and treatment of latent iron deficiency. The aim of the work was to analyze and systematize the main problematic issues of diagnosis and treatment of iron deficiency anemia in children. To conduct the study, we analyzed databases PubMed, Cochrane Library, Google Scholar, etc., referring to the vast majority of publications from the last five years (2016-2021), in addition to three articles published in 2012 and 2014. The main criteria for selecting sources were: the availability of the latest methods for the diagnosis of anemia, modern methods of treatment of iron deficiency anemia in children. Analysis of the identified literature sources showed that iron deficiency in the laboratory and clinically can manifest itself at different stages. Negative iron balance, which persists after a decrease in iron stores, is manifested by a decrease in hemoglobin and the development of anemia. A decrease in the number of erythrocytes or the level of hemoglobin (Hb) by 5 percentile below the normal value of hemoglobin, determined for a given age in healthy people, is called anemia. Routine screening for iron deficiency should be performed in children aged 6 to 24 months. Screening consists of identifying risk factors and laboratory testing if available. Determination of serum ferritin during the first screening is the main diagnostic tool in children with risk factors for iron deficiency and signs of anemia. Ferritin levels should always be carefully evaluated, as ferritin is nonspecifically elevated in a variety of inflammatory conditions. Other screening tests, such as reticulocyte levels, iron transferrin saturation, and serum iron-binding capacity, are performed to confirm the diagnosis. The choice and route of administration of iron requires consideration of the cause that led to its deficiency, the severity of symptoms and condition of the patient, the probable and desired rate of hematological response, risks and complications of treatment, availability of resources and preferences of the patient. Oral iron remains a priority for the treatment of children with iron deficiency anemia, but it is necessary to consider situations where first-line therapy will be administered by intravenous means. Thus, based on the analysis of the literature, we can conclude that iron deficiency anemia remains an urgent medical and social problem today. Children with iron deficiency anemia develop cognitive impairment that does not fully recover even after treatment. Therefore, further research aimed at improving methods of prevention, early diagnosis and treatment of iron deficiency anemia in different age groups of children should be promising.