Objective: to analyze the relationship between the knowledge, prevention, attitudes and opinion of nursing professionals in adult intensive care units regarding COVID-19 and their sociodemographic and work characteristics. Method: cross-sectional, analytical study. 124 nursing professionals who worked in adult intensive care units after the COVID-19 pandemic were included. To measure the variables, the Awareness, Attitudes, Prevention and Perceptions of COVID-19 Outbreak among Nurses questionnaire was used. To identify differences between the groups, the following tests were used: Kruskal-Wallis and Mann-Whitney U, Pearson correlation, and multiple analysis in logistic regression for each dimension. Results: participants with a workplace in private institutions showed a tendency towards better scores in awareness OR=3.92 (95%CI:1.50; 10.25), in prevention OR=8.93 (95%CI:3.12; 25.565), in attitude OR=2.77 (95%CI: 1.16; 6.58) and in perception with an OR= 19.65 (95%CI: 5.85; 65.94). In attitude, male participants showed a better result with OR=3.31 (95%CI: 1.18; 9.23) and in relation to perception, those who showed the best results were those with postgraduate studies as specialists OR=7.60 (95%CI: 1.73; 33.23). Conclusion: working in a private institution and having a postgraduate specialization degree were related to better scores in the dimensions of the scale.