BACKGROUND: For a long time in the Russian Federation, there was a problem of the lack of registry of anaphylaxis, as the most important tool for recording and monitoring this group of patients. Since 2022, the first Pediatric Moscow Anaphylaxis Registry has started working at the Morozov Children's Hospital. AIM: Objectification and analysis of data from the Pediatric Moscow Anaphylaxis Registry to determine the frequency, causes and characteristics of anaphylaxis clinical symptoms among children of the Moscow region. MATERIALS AND METHODS: The statistical analysis of the questionnaire data of the patient-oriented questionnaire of 69 children aged 0 to 18 years, who were prospectively included in the Register during emergency hospitalization due to anaphylaxis, was carried out. RESULTS: The incidence of anaphylaxis among children hospitalized with acute allergic reactions from May 2022 to September 2023 was 5.8%. A higher percentage of anaphylaxis episodes (38%) were observed among adolescents aged 13–18 years, three patients developed anaphylaxis in the first year of life (minimum age 1 month). Boys (70%) prevailed among patients with anaphylaxis under the age of 13, and girls (56%) prevailed among adolescents aged 13–18 (p=0.042). In 75%, anaphylaxis developed at home. For patients of all age groups, food anaphylaxis was dominant (75–91%). Tree nuts were the most common suspected trigger of food anaphylaxis ― 35% of reactions, and confectionery products in 17% of cases. With anaphylaxis, 56% of children experienced symptoms from four or more organ systems, the most common symptoms were from the skin/mucous (94%), respiratory organs (78%) and laryngeal symptoms (64%). At the stage of emergency medical care, the frequency of diagnosis of anaphylaxis was 22%, and the administration of epinephrine was 54%. The frequency of epinephrine use among children under 3 years of age was lower compared to adolescents aged 13–18 years (25% vs 76%, p=0.003) CONCLUSION: The data from the work of the first Pediatric Moscow Anaphylaxis Registry in the Russian Federation demonstrate a high incidence of anaphylaxis among patients with acute allergic reactions. More than 1/3 of anaphylactic reactions occur in adolescents aged 13–18 years, while anaphylaxis occurs even in the first month of life. Anaphylaxis most often develops at home, which dictates the special need for careful training of patients in the rules of elimination of the trigger. The dominant cause of anaphylaxis in children in the Russian Federation, regardless of age, are food allergens, tree nuts induce anaphylaxis in more than 1/3 of cases. The frequency of diagnosis of anaphylaxis at the stage of emergency medical care does not exceed 22%, administration of epinephrine ― 54%, minimal use of epinephrine is observed among children under 3 years of age.