Use of unclaimed bodies for anatomy teaching in undergraduate medical education continues, but is ethically controversial. The purposes of this study were to estimate the proportion of United States (US) medical schools using unclaimed bodies in first-year anatomy laboratories, to determine whether schools inform students of this use, and to explore anatomy course leaders' attitudes toward unclaimed body use. Anatomy course leaders from 146 US medical schools that had independent preclinical programs including anatomy were surveyed. Survey results were analyzed with descriptive statistics and statistical tests of association. Free text responses were analyzed using a thematic editing style of qualitative content analysis. Of 89 responses (response rate, 61.0%), 11 schools (12.4%) reported possible use of unclaimed bodies. Course leaders from these schools reported greater comfort with using unclaimed bodies compared to leaders from other schools (P < 0.01). Although most course leaders (49/76, or 64.5%) believed it was important or very important to inform students about use of unclaimed bodies, respondents from schools where unclaimed bodies could be used were more neutral (P < 0.01). Qualitative findings revealed deep disagreement and contradictory views about how unclaimed body use relates to ethical principles of respect for persons and justice. Continued use of unclaimed bodies, varying levels of comfort with their use, and disagreement about the practices' underlying morality suggest a need for greater ethical reflection about the permissibility of unclaimed body use in clinical anatomy and for educational interventions that teach students about its history, ethics, and contemporary practice.