The most severe manifestation of the new coronavirus infection COVID-19 in children is the multisystem inflammatory syndrome in children (MIS-C). A systematic review of foreign publications as of July 25, 2020 contains an analysis of the disease course in 662 children with this syndrome and is used for comparison with the data obtained. Objective of the research: to characterize clinical manifestation, results of laboratory and instrumental studies, therapy, outcomes and consequences of the COVID-19-associated MIS-C, based on the observation of patients hospitalized to Morozov Children's City Clinical Hospital and Children’s clinical hospital of infectious diseases № 6 from May 1 to September 15, 2020. Materials and methods: the pilot study included 32 children aged 9 months – 15 years with COVID-19-associated MIS-C, verified based on WHO criteria (2020), including symptoms of Kawasaki disease (KD), arterial hypotension/shock, laboratory and instrumental signs of heart damage, signs of coagulopathy, gastrointestinal symptoms, increased inflammation markers, COVID-19 markers. Results: the median age of patients was 6 years, boys predominated among the patients (66%), all patients had antibodies to SARS-CoV-2 (31 children of the IgG class); MIS-C manifested itself as a combination of KD symptom complex (75% of patients) with arterial hypotension/shock (28%), neurological (50%), respiratory (41%), gastrointestinal (59%) symptoms; macrophage activation syndrome (MAS) was verified in 16% of patients. Therapy included intravenous immunoglobulin (75%), systemic glucocorticosteroids (88%), anticoagulants (91%), vasoactive/vasopressor support (31%). In 38% of cases treatment was performed in intensive care unit; one child died. According to echocardiography, 16% of patients had coronariitis, ectasia, and coronary arteries aneurysms. Conclusion: COVID-19-associated MIS-C is characterized by a severe course, cross-features with KD, shock syndrome with KD, MAS which requires intensive therapy and can cause acquired pathology of the cardiovascular system in children. © 2020, Pediatria Ltd. All rights reserved.