The notion of physician invulnerability to illness contributes to the ongoing marginalization of physicians with personal experiences of illness and complicates professional identity development in medical learners. As such, physician self-disclosure of lived experiences as patients has seen an increasing role in medical education. Existing literature, centered on mental health, has characterized the positive effect of physician discussion of experience with mental illness on medical students and residents. However, the ways learners process and understand physician illness stories beyond this context and their use in education remain unclear. This study aimed to explore undergraduate medical students' perspectives on physician illness discussions of both physical and mental illness, including their perceptions of its use as a pedagogical tool. This qualitative study followed an interpretive descriptive design using activity theory as a sensitizing concept. Semistructured interviews with medical students were conducted between January and April 2022 at McMaster University in Hamilton, Ontario, Canada. The authors analyzed transcripts using reflexive thematic analysis. Twenty-one medical students participated in interviews. Although rare, self-disclosure conversations occurred across varied settings and addressed diverse aspects of illness experiences. Discussions involved teaching of pathophysiology, career advice, and wellness guidance. Five themes were developed: the opposition of physicianhood, patienthood, and situating the learner identity; invisibility and stigmatization of physician illness; impact of preceptor stories on learners' relationship with medicine; challenging the "rules" of physicianhood; and situating self-disclosure in medical education. Students strongly appreciated physician self-disclosure conversations. Self-disclosure can act as an effective pedagogical tool by fostering expansive learning among medical students. Further research is necessary to explore physician perspectives and supports for self-disclosure in education.