Abstract Exercise is a first-line treatment for chronic low back pain (CLBP), reducing pain and disability in the short term. However, exercise benefits decrease over time, with a lack of long-term exercise adherence a potential reason for this. This study aimed to synthesize the perceptions and beliefs of individuals with CLBP and identify their barriers and enablers to exercise adherence. We searched CENTRAL, Embase, CINAHL, SPORTDiscus, PubMed, PsycINFO, and Scopus databases from inception to February 28, 2023, for qualitative studies that explored the factors influencing exercise adherence for people with CLBP. A hybrid approach combining thematic synthesis with the Theoretical Domains Framework was used to analyze data. We assessed methodological quality using the Critical Appraisal Skills Programme checklist and the level of confidence of the themes generated using the Confidence in the Evidence from Reviews of Qualitative Studies. Twenty-three papers (n = 21 studies) were included (n = 677 participants). Four main themes affected exercise adherence: (1) exercise, pain, and the body, (2) psychological factors, (3) social factors, and (4) external factors. These themes contained 16 subthemes that were predominantly both barriers and enablers to exercise adherence. The individual's experiences of barriers and enablers were most appropriately represented across a spectrum, where influencing factors could be a barrier or enabler to exercise adherence, and these could be specific to pre-exercise, during-exercise, and post-exercise situations. These findings may be used to improve exercise adherence and ultimately treatment outcomes in people with CLBP.