A new original Russian test kit for the detection of IgG-antibodies to the causative agent of COVID-19 - coronavirus SARS-CoV-2 by the method of enzyme-linked immunosorbent assay (ELISA) on a solid-phase « ELISA-SARS-CoV-2-AT-G¼ has been developed . In comparative tests with similar test systems « Vitrotest® SARS-CoV-2 IgG¼ (Vitrotest, Ukraine) and « Anti-SARS-Cov-2 ELISA (IgG) ¼ (EUROIMMUN AG, Germany) high diagnostic efficiency of the new test system was shown.