ABSTRACT OBJECTIVE: to understand how nurses describe the challenges and construction of knowledge related to the care provided to people with post-COVID-19 syndrome. METHOD: this is qualitative-descriptive research, guided by the social constructionist perspective, carried out with seven nurses in a 24-hour Emergency Care Unit located in Minas Gerais. Data were collected from March to June 2022 through recorded semi-structured interviews. Data analysis took place through the transcription of interviews, followed by a curious reading of the material and definition of categories, step-by-step, anchored by social constructionism. The theoretical framework was composed of the set of authors who helped in the analysis and discussion of the categories constructed to respond to the study objectives. RESULTS: four categories emerged from the interviews, namely: 1) Initial reflexes of the pandemic, in which nurses’ feelings of fear, concern and insecurity were evidenced; 2) COVID-19 traces, of which the respiratory sequels caused by the disease stood out; 3) Knowledge about post-COVID-19 syndrome, which detected lack of knowledge about signs and symptoms and nursing care, due to lack of training and use of protocols; 4) Care for post-COVID-19 syndrome, which highlighted the lack of knowledge about referring people to rehabilitation services. CONCLUSION: despite the lack of protocols and training provided by the institution, nursing professionals provided assistance care on knowledge provided by their experiences and the exchange of experiences with other collaborators.