Background and Purpose: Ethical climate is hinged upon organizational culture, rules, and policies; nurses' perception of this concept varies according to the ward they are working on and the new rules of the treatment system. This can exert adverse impact on their care method and performance. Thus, this study aimed to determine nurses' perceptions of the ethical climate governing the hospital environment. Methods: This descriptive, cross-sectional study was conducted on 168 nurses working in a teaching hospital. The data were collected through census method, using a demographic form and Olson's Hospital Ethical Climate Survey (HECS). For data analysis, descriptive (percentage, frequency, mean, and standard deviation) and inferential statistics (independent t-test and ANOVA for the establishment of the relationship between ethical climate and demographic factors, as well as Friedman's test for ranking the factor) were used. Results: Mean ethical climate scores of nurses for managers, hospital, physicians, patients, and colleagues factors were 3.87±0.71, 3.39±0.68, 3.00±0.67, 3.68±0.57, and 3.82±0.54, respectively. The total mean score of ethical climate was 3.5±0.51. The comparison among the mentioned factors indicated that managers (P=0.000) factor acquired the highest score. In addition, organizational ethical climate did not show any significant association with gender, marital status, education level, working shift, and employment status, whereas there was a statistically significant relationship between job title and income (P=0.000). Conclusion: The highest score of ethical climate belonged to managers/ factor, while the minimum score was related to physicians. Regarding the role of ethical climate in the improvement of nurses' performance, planning for enhancing the ethical climate seems to be mandatory.