For medical teams, one of the main objectives of rehabilitation for people with chronic low back pain is adherence to physical activity (PA). The objective of this study was to identify PA barriers and facilitators in this population. This qualitative study included 4 discussion groups and 16 semi-structured interviews conducted among people with non-specific chronic low back pain who were involved in a specific rehabilitation program or seen in primary care settings. Three main themes were identified: physical factors, psychological factors and socio-environmental factors. The main barrier to PA practice is pain. Psychological barriers were associated with the difficulty in integrating PA in the person’s daily life. Environmental barriers were dominated by lack of time. Facilitators identified associated the supervised nature of the physical activity (supervision by professionals) and group practice, which improved people’s adherence. The results of this study will allow teams to target relevant educational objectives for these people and develop dedicated self-management programs.