Purpose: The purpose of this qualitative study was to explore the experiences of post-traumatic growth in breast cancer survivors by applying grounded theory methods. Methods: Participants were seven breast cancer survivors who had been diagnosed with stage I or higher breast cancer, had completed acute treatment, and were members of an internet self-help group for breast cancer survivors. Data were collected through individual in-depth interviews from July 11, 2022 to May 4, 2023. The interview contents were transcribed and analyzed using Corbin and Strauss’s grounded theory method. A total of 18 sub-categories and 9 categories were identified through the open coding process. Results: As a result of axial coding based on the paradigm model, the central phenomenon of post-traumatic growth experiences of breast cancer survivors was revealed as ‘Finding true life after the pain of death’. The core category was identified as ‘Promise a life without regrets’, which consisted of a four-step process: reflection period, recovery period, transition period, achievement period. Breast cancer survivors experienced restoration of their inner selves, strengthening of positive thinking through the process of resetting their life values and goals, and pursuit a stable and satisfying life. Conclusion: To help breast cancer survivors grow after trauma, the importance of accepting changes in their bodies and maintaining a positive perspective was highlighted.