BackgroundDue to their constant exposure to complex clinical situations, nurses face numerous ethical challenges that can significantly impact their clinical decision-making. Moral disengagement is one such challenge, whereby nurses become detached from their professional values and ethical principles. Understanding this phenomenon is crucial for improving ethical practice and supporting nurses in maintaining moral integrity in demanding healthcare environments.AimThis phenomenological study aimed to explore Iranian nurses' experiences of moral disengagement in clinical practice.Research designA qualitative study with an interpretative phenomenological approach was conducted. A total of 18 nurses working in university hospitals in Iran were selected via purposive sampling. Data were collected through in-depth, semi-structured, face-to-face interviews and analyzed using Diekelmann's interpretative phenomenological method.Ethical considerationsThis study was approved by the local Ethics Review Committee. Each participant provided written informed consent. Confidentiality was ensured through anonymization of transcripts, secure data storage, and the use of participant codes.FindingsData analysis resulted in four main themes and ten subthemes. The main themes include "Detachment from the ethical value system," "Moral instability in the shadow of professional challenges," "Echoes of a presence void of commitment," and "The necessity of reviving forgotten ethical ideals."ConclusionMoral disengagement is a complex, multifaceted phenomenon that stems not only from personal attributes but also from structural, cultural, and organizational challenges within the healthcare system. To prevent and address this issue in the Iranian context, it is essential to foster moral identity, rebuild supportive organizational climates, and restore a meaningful sense of caregiving within the nursing profession through targeted education, ethical leadership, and systemic reforms.