Purpose <p>With the ageing population, more older persons require rehabilitation following (sub)acute functional decline. The International Classification of Functioning, Disability and Health (ICF) model offers a biopsychosocial framework to address complexities of rehabilitation in this population. This systematic review investigates which ICF components have been reported in rehabilitation research involving older persons, which rehabilitation outcomes have been reported, and whether, and how associations between ICF components and rehabilitation outcomes have been described.</p> Methods <p>A comprehensive search was conducted in three databases. Studies involving older persons (mean or median age ≥ 70&#xa0;years) undergoing post-acute rehabilitation, with health data linked to the ICF model and rehabilitation outcomes, were included. Study quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) by two independent reviewers.</p> Results <p>Seven studies involving 896 patients were included. Associations were found between ICF components, particularly body functions and activities and participation, and improved functional independence and quality of life. Environmental factors also contributed to outcomes, whereas personal factors did not appear, reflecting their absence from the formal ICF coding structure.</p> Conclusion <p>This review shows that body functions and activities and participation are most consistently linked to clinical outcomes in older persons, reflecting their central role in functional independence and quality of life. Environmental factors were examined less often, yet contextual factors (including personal factors) remain important for understanding recovery and personalized care. These findings clarify which ICF-based functional profiles are routinely captured and support more structured, person-centred assessment across the rehabilitation trajectory. Further research should include personal factors and longer-term outcomes.</p>