Broncho-pulmonary diseases in children is one of the urgent problems in pediatrics, which is determined by the continuing high incidence and severe prognosis, especially in young children. The aim of the study was to determine the clinical characteristics of acute myocarditis in children with acute broncho-pulmonary diseases. We examined 84 children aged 6 months to 6 years with broncho-pulmonary diseases, which we divided into 2 groups. Group I (control) included 42 children who had only respiratory complaints. Group II (main) included 42 sick children with broncho-pulmonary diseases, who had a violation of the cardiovascular system, the presence of which was confirmed by instrumental methods. The results obtained emphasize that against the background of broncho-pulmonary diseases, all symptoms of acute heart failure are masked, the cause of which in most cases is acute coronary insufficiency; changes in the heart muscle in this pathology in children increases the risk of severe unwanted heart complications.