Background: Ethical climate and moral distress have been shown to affect nurses’ ethical behaviour. Despite the many ethical issues in paediatric oncology nursing, research is still lacking in the field. Research aim: To investigate paediatric oncology nurses’ perceptions of ethical climate and moral distress. Research design: In this cross-sectional study, data were collected using Finnish translations of the Swedish Hospital Ethical Climate Survey–Shortened and the Swedish Moral Distress Scale–Revised. Data analysis includes descriptive statistics and non-parametric analyses. Respondents and research context: (...) Ninety-three nurses, working at paediatric oncology centres in Finland, completed the survey. Ethical considerations: According to Finnish legislation, no ethical review was needed for this type of questionnaire study. Formal research approvals were obtained from all five hospitals. Return of the questionnaire was interpreted as consent to participate. Results: Ethical climate was perceived as positive. Although morally distressing situations were assessed as highly disturbing, in general they occurred quite rarely. The situations that did appear often reflected performing procedures on school-aged children who resist such treatment, inadequate staffing and lack of time. Perceptions of ethical climate and frequencies of morally distressing situations were inversely correlated. Discussion: Although the results echo the recurrent testimonies of busy work shifts, nurses could most often practise nursing the way they perceived as right. One possible explanation could be the competent and supportive co-workers, as peer support has been described as helpful in mitigating moral distress. Conclusion: Nurturing good collegial relationships and developing manageable workloads could reduce moral distress among nurses. (shrink)