Background Frontline nurses who care for patients with COVID-19 work in stressful environments, and many inevitably struggle with unanticipated ethical issues. Little is known about the unique, ethically sensitive issues that nurses faced when caring for patients with COVID-19. Aim To better understand how frontline nurses who care for patients with COVID-19 experience ethical issues towards others and themselves. Methods Systematic review of qualitative evidence carried out according to the Preferred Reporting Items for Systematic reviews and Meta-analyses on ethical literature (...) (PRISMA-Ethics). The electronic databases PubMed, Embase, Cinahl, Web of Science, Philosopher's Index, and Scopus were queried to identify candidate articles. Articles appearing from March 1, 2020 to December 31, 2022 were considered if they met the following inclusion criteria: (1) Published qualitative and mixed method studies and (2) ethical issues experienced by nurses caring for patients with COVID-19. We appraised the quality of included studies, and data analysis was guided by QUAGOL principles. Findings Twenty-six studies meeting our inclusion criteria for how nurses experience ethical issues were characterised by two key themes: (1) the moral character of nurses as a willingness to respond to the vulnerability of human beings and (2) ethical issues nurses acted as barriers sometimes, impeding them from responding to requests of vulnerable human beings for dignified care. Conclusion Our review provides a deeper understanding of nurses’ experiences of ethically sensitive issues, while also highlighting the critical need for adjustments to be made at organisational and societal levels. Ethical issues that emerged in situations where organisational and situational constraints impeded nurses' ethical responses to patients’ appeals suggests that early practical support should be made available to resolve ethical issues recognised by nurses. Such support contributes to protecting and promoting not only the dignity of patients with COVID-19 but also of fellow humans in need during crisis. (shrink)