Background <p>Post-liver transplant metabolic syndrome is a common complication that threatens long-term outcomes. Exercise is a cornerstone of non-pharmacological management, yet adherence remains low. Guided by the COM-B framework, this study explored the barriers and facilitators of exercise behaviors to inform rehabilitation nursing strategies.</p> Methods <p>A qualitative study was conducted with 16 liver transplant recipients diagnosed with metabolic syndrome at a tertiary transplant center in China. Semi-structured interviews were used to capture patients’ experiences with exercise during postoperative rehabilitation. Data were analyzed thematically within the COM-B framework to identify behavioral determinants across capability, opportunity, and motivation domains.</p> Results <p>Barriers included limited physical capacity, misconceptions about exercise safety, and financial constraints, while facilitators involved time autonomy, digital literacy, and standardized education. Opportunity barriers were lack of structured guidance, unreliable information, and competing demands; facilitators included accessible digital resources, multi-level support, and convenient environments. Motivation barriers encompassed misperceptions, avoidance tendencies, and knowledge access issues, while facilitators included health threat awareness, positive experiences, trust in professionals, and engaging health livestreams.</p> Conclusion <p>Rehabilitation nursing plays a pivotal role in addressing behavioral barriers and leveraging facilitators to enhance exercise adherence in liver transplant recipients with metabolic syndrome. Integrating COM-B informed insights into rehabilitation care through personalized education, digital support, and multi-level social reinforcement offers practical pathways to promote sustainable lifestyle change and improve long-term recovery and quality of life.</p> Clinical trial number <p>Not applicable. This study did not involve a clinical trial.</p>