Background Ethical nurse leaders play a pivotal role in helping their nurse employees deliver high-quality healthcare services. However, we still lack a comprehensive understanding of the mediating and moderating mechanisms by which ethical leadership improves job performance. Purpose This study aims to investigate: (1) whether ethical leadership would enhance nurses’ job performance; (2) whether learning goal orientation acts as a mediator; and (3) whether co-worker support operates as a moderator. Participants and research context We collected two-wave data from 218 nurses (...) working in hospitals located in Jiangsu, China. Research design A time-lagged study based on an online survey design was utilized for data collection between September 2022 and January 2023. PROCESS Model 5 was employed to test the research hypotheses. Ethical considerations We obtained ethics approval from the University Ethics Committee. The nursing participants were assured that their survey responses were completely anonymous. Results and discussion Ethical leadership is not significantly correlated with job performance. However, ethical leadership has an indirect impact on nurses’ job performance through the mediator (learning goal orientation). Moreover, co-worker support moderates the relationship between ethical leadership and job performance. Conclusion The conceptual model provides us with a fine-grained understanding of the relationship between ethical leadership and nurses’ job performance. We highlight the mediating role of learning goal orientation and the moderating role of co-worker support. We suggest that healthcare organizations should devote more efforts to promoting ethical leadership, co-worker support, and learning goal orientation. (shrink)