Virtual patients (VPs) are increasingly used in health professions education. How learners engage with VPs and the relationship between engagement and authenticity is not well understood. We explored learners' perceptions of VP education to gain an understanding of the characteristics promoting meaningful engagement in learning, including perceived authenticity. Using a constructivist grounded theory approach, we conducted interviews and focus groups with 11 students from 2 Canadian Physician Assistant programs, where VP learning was implemented to supplement clinical education during the COVID-19 pandemic. We explored trainee perspectives on the use of VPs as an educational modality. Data were iteratively collected and descriptively analyzed thematically using a constant comparison approach until theoretical sufficiency was reached. We identified 3 groups of factors influencing these students' VP learning experiences: (1) technical factors related to the VP platform influenced the perceived authenticity of the patient interactions; (2) individual factors of learners' attitudes influenced their engagement and motivation; and (3) contextual factors related to the learning environment influenced the acceptability and perceived value of the learning experience. Overall, the psychological authenticity of the learning platform and students' motivation for self-directed learning were perceived as most important for students' learning experiences. Implementing VP learning as a supplement to clinical education should be done with consideration of factors that enhance the psychological authenticity of the learning platform, promote learner engagement and accountability, and encourage acceptability of the learning modality through curricular placement and messaging.