Background: Lung cancer is the most common cancer and leading cause of cancer death worldwide. In lung cancer clinical trials, overall survival (OS) is a widely used endpoint; however, DFS – the time to cancer recurrence or death from any cause – may be a better indicator of transformative patient outcomes. While the use of DFS is growing, patient perceptions of the validity of this endpoint have not been established. Objective: To understand the importance of DFS as a treatment endpoint, from the perspective of Canadian lung cancer survivors. Methods: This qualitative study included Canadian survivors of stage Ib to IIIa lung cancer, who participated in web-based semi-structured interviews in early 2021. Participants described their experience of cancer diagnosis and treatment and provided their perspectives on DFS and OS, including how well each endpoint aligned with their own treatment priorities. Thematic analysis was used to explore patterns in responses. Results: Of 14 participants, the mean age was 64 years, 14% were male, 86% had surgery and 58% were treated with chemotherapy. Most participants viewed DFS as intrinsically relevant to their treatment priorities. One individual’s interest in DFS was limited to its ability to serve as a surrogate for OS. All participants emphasized that new treatments should be quickly approved based on DFS when OS data are not yet available; an issue that was often viewed in the context of promoting patient agency in treatment decision-making. Conclusions: These findings validate DFS as a meaningful endpoint from the perspective of lung cancer survivors and highlight patients’ desire for rapid approval of treatments that have been demonstrated to improve DFS.