This study aimed to explore research trends of nursing ethics in Korea applying text network analysis and topic modelling. 306 articles published in KCI journals from 1998 to 2021 were identified and 516 author-provided keywords were collected. A co-occurrence matrix with 123 keywords, which appeared at least in two articles, were developed based on the Jaccard coefficient. Degree centrality and betweenness centrality were calculated and LDA topic modelling were performed using NetMiner software. The largest number of the articles (70, 23%) were published in Korean Journal of Medical Ethics. The most critical core-keywords, defined as the top 30 keywords in degree centrality and betweenness centrality, were ‘nursing students’ and ‘moral sensitivity’. The other core-keywords included ‘attitude,’ ‘awareness,’ ‘professionalism,’ ‘knowledge,’ and ‘critical thinking.’ related to ethical competence, ‘death,’ ‘hospice,’ ‘euthanasia,’ and ‘research ethics’ related to bioethical issues, and ‘job satisfaction,’ ‘burn out,’ ‘stress,’ ‘organizational culture,’ ‘ethical leadership,’ and ‘ethical climate’ related to organization and leadership. Five topics were identified and named as a) bioethics education for nursing students, b) knowledge and attitudes for bioethical issues, c) awareness and values of bioethics, d) ethical conflicts of RNs, and e) nursing ethics education. This study found that bioethics was the main topics in Korean nursing ethics research and suggested nursing research should focus on ethical issues RNs frequently experience in patient care. Also, research gaps were inferred in multiple topics including nurse-to-nurse relationships, theoretical perspectives of virtue ethics and care ethics, or witnessing healthcare professionals’ unethical behavior.