The review presents data on the features of COVID-19 infection course in children of different ages. It has been shown that children carry the disease much easier than adults. However, the younger the child, the more often he has a severe infection. Infants and newborns suffer the most severe COVID-19 disease. In the future, the older the child (up to 18 years old), the easier his illness progresses, less often severe pneumonia accompanied by acute respiratory respiratory syndrome (ARDS) occurs and there is practically no multiple organ. The most common symptoms in affected children with COVID-19 are short-term fever, easy fatigue, myalgia, nasal congestion, runny nose, sneezing, sore throat, headache, and dizziness. Less common is nausea, vomiting, abdominal pain, diarrhea. In children, in contrast to adults, neutrophilia, thrombocytopenia, lymphocytopenia occur less often, the content of pro-inflammatory cytokines increases moderately, and only in isolated cases does the state of cytokine storm occur. In children, it is extremely rare for the D-dimer to reach high numbers, indicating the presence of intense intravascular blood coagulation. Therapy for children with COVID-19 should be based on the severity and age of the child. A significant role in the fight against COVID-19 is assigned to immunocorrective drugs (INF-γ, tocilizumab, azithromycin, doxycycline, etc.) and antiviral drugs (favipiravir, etc.) play a significant role in the fight against COVID-19. We believe that thymalin, which has proven itself well in pneumonia and various infectious diseases in both adults and children.