Background Managerial ethical principles and behaviours guide the roles, duties, responsibilities, behaviours, and relationships of nurse managers in healthcare institutions. Research objectives The aim of this study was to establish the managerial ethical principles and behaviours for nurse managers. Research question What are the managerial ethical principles and behaviours for nurse managers? Research design The Delphi method, one of the qualitative research methods, was used in this study. The Delphi process consisted of two rounds. Data were collected by e-Delphi technique. (...) Participations 42 experts were included in the first Delphi round and 39 in the second Delphi round. These experts consisted of nurse managers, academicians studying in the field of ethics and nursing management. Ethical considerations Participation in the study was voluntary and informed consent of the experts was obtained before the study. Approval was obtained from the ethics committee of the university at which the researcher worked (Approval date: 24.07.2020, Decision No: 2020/12-16). Findings At the end of the Delphi rounds, eight managerial ethical principles and 29 ethical behaviours of these principles were identified. The distribution of these behaviours and principles were: justice (six behaviours), equality (two behaviours), honesty (two behaviours), fairness (two behaviours), responsibility (eight behaviours), confidentiality (two behaviours), clarity (two behaviours), and humanity (five behaviours). Conclusion These managerial ethical principles and behaviours are intended to guide nurse managers when providing nursing services but should be updated accordingly in line with changing conditions and developments. (shrink)