Objective: to know the factors that exert an influence on the health professionals’ perception of the risk of becoming contaminated with COVID-19 in Brazil. Methods: a survey conducted from May to October 2020 with 436 active health professionals working in the front line against COVID-19. Descriptive analyses were used and a structural equation model from an exploratory factor analysis was estimated. Results: the health professionals’ perception on contracting COVID-19 was considered as medium to very high for 72% of the respondents. In the structural equation model, knowledge of the treatment for COVID-19, preparation of the health professionals to work, and safety in the institutional protocol together with confidence in official protocols and disclosures through social, printed and television media exerted an influence on confidence to face the pandemic (P<0.05). This self-confidence along with the male gender were significant determinants (P<0.001) for the perception of the possibility of becoming contaminated. Conclusion: this study may contribute to the realization of strategies, public policies and guidelines that may impact on improving self-confidence and protecting the health professionals in their performance during the COVID-19 pandemic.