Introduction:Courage is the ethical virtues that has special place in the nursing profession, whose role in patient support is highlighted. Courage virtues seems to grow with environmental reinforcement and social support. Hospital as a dynamic social institution has different forms of ethical climates. The purpose of this study was to determine the correlation between the ethical climate of the hospital and the moral courage of the nurses in one of the medical universities of Iran medical science's selected hospitals. Method: This study is a descriptive-correlational study. The sample included 156 nurses who were selected by available method. A translated questionnaire of Olson's ethical climate and Sekerka's et al moral courage was used to collect data, in addition to demographic questions. The data were analyzed by SPSS software version 21 using descriptive and inferential statistics. Findings: Nurses' perception of the ethical climates of the hospital was average (mean= 3.79, SD = 0.56) and their courage was moderate (mean 3.87, SD=0.86). There was a significant positive correlation between nurses' ethical climates and their moral courage (r = 0.90, p <0.001). Conclusion: According to the findings of this study, the moral courage virtue of nurses in ethical climates of support and care grows well. Therefore, to improve the role of protecting patients' rights and promote moral courage, attention should be paid to improving the ethical climates of the hospital. In addition, planners and nursing managers should consider arrangements for developing the ethical climates of the workplace.