Background: Silesia is one of the regions in Poland most affected by the COVID-19 epidemic. The high number of infections among the inhabitants of the region increases the already high risk of infection of SARS-CoV-2 virus of medical workers who, due to their work, are more likely to be exposed to people with SARS-CoV-2 than people from the general population. The aim of this study is to assess the prevalence of SARS-CoV-2 infection among healthcare workers in the Upper Silesia Metropolitan Area based on the results of a seroepidemiological study. Material and Methods: The seroepidemiological study was carried out in October– November 2020 among the inhabitants of the Upper Silesia Metropolitan Area (including medical professionals who were selected, creating a research group of healthcare workers). Apart from the questionnaire examination necessary to determine the declared symptoms, circumstances and risk factors conducive to infection, the level of specific antibodies against the SARS-CoV-2 virus in the IgG and IgM class was assessed. Results: In the study participated 575 people declaring their medical profession. A positive test for the presence of IgG antibodies was confirmed in 19.1% of the respondents, while a positive test for IgM concerned 4.3% of the subjects. The most common positive results indicating infection with the SARS-CoV-2 virus concerned people declaring prior contact with an infected person (p = 0.001) and those undergoing quarantine (p < 0.0001). Conclusions: The frequency of SARS-CoV-2 virus infections in medical personnel in the Upper Silesia Metropolitan Area, assessed on the basis of a positive IgG antibody test result, was 16.1–22.5%. Med Pr. 2022;73(2):125–33