ObjectiveTo investigate the chain effect of moral leadership and ethical climate on moral distress and moral injury. MethodsA total of 606 nurses in Shandong Province， China， were selected using a convenience sampling method at August 2023. Participants were evaluated using the Moral Distress Scale， the Moral Injury Symptoms Scale， the Moral Leadership Measure， and the Hospital Ethical Climate Survey. ResultsThis study provided a model describing the interrelationships among moral distress， moral leadership， ethical climate， and moral injury. Moral distress had a negative impact on moral injury， while moral leadership and ethical climate had positive effects on both moral distress and moral injury. Moreover， moral leadership and ethical climate could moderate the relationship between moral distress and moral injury， playing a partial mediating role. The final model showed that moral distress， moral leadership， ethical climate， and moral injury formed a chain effect. ConclusionNursing managers and nurses should actively participate in moral training and education to enhance their ability to address moral distress. Meanwhile， healthcare organizations should cultivate moral leaders， improve the ethical climate in the workplace， promptly identify and intervene in moral injury， and maintain nurses’ mental health.