Background: The ethical challenges faced by undergraduate nursing students and nurses may lead to moral distress, negatively affecting learning capacity and self-confidence and potentially influencing the quality of patient care. Objective: To examine the state of knowledge regarding the moral distress among undergraduate nursing students during clinical practice. Methods: This scoping review followed JBI guidelines. First, the LILACS, Web of Science, Scopus, CINAHL, PubMed/MEDLINE, PsycINFO, Embase, and ProQuest databases were consulted. Next, the reference lists of the studies included in the (...) sample were checked. Studies exploring moral distress among undergraduate nursing students during clinical practice were included regardless of language or date of publication. Two independent reviewers simultaneously selected the studies. Results: The sample included 12 articles with different research designs. Three conditions that trigger moral distress among undergraduate nursing students emerged: Interpersonal relationships between students and preceptors/supervisors and multidisciplinary teams; interpersonal relationships between students and patients; and the relationship between students and health services. Conclusions: This review identified the various circumstances that lead to moral distress among undergraduate nursing students. Therefore, these results highlight the importance of preventing moral distress in this group through teaching, especially before students begin their clinical practices. (shrink)