BACKGROUND: Hospital readmissions pose significant burdens on healthcare systems, particularly among older adults. While efforts to reduce readmissions have historically focused on medical management, emerging evidence suggests physical function may also play a role in successful care transitions. However, there is a limited understanding of the relationship between functional measures and readmission risk. This systematic review aims to assess the association between physical function impairments and hospital readmissions. OBJECTIVE: This systematic review aims to assess the association between physical function impairments and hospital readmissions. METHODS: A systematic review was conducted following PRISMA guidelines, with studies identified through databases including PubMed, CINAHL, Embase, and others published January 1, 2010-December 31, 2022. Inclusion criteria encompassed observational studies of adults aged 50 and older in the United States, reporting readmissions within 90 days of discharge and assessing physical function across domains of the International Classification of Function model. Data extraction and risk of bias assessment were independently conducted by two authors using the Scottish Intercollegiate Guidelines Network (SIGN) tool. RESULTS: Seventeen studies, representing 80,008 participants, were included in this systematic review. Patient populations included a wide array of medical populations, including general medical inpatients and those undergoing cardiac surgery. Across various functional measures assessed before or during admission, impairments were consistently associated with increased risk for hospital readmissions up to 90 days after admission. Measures of participation, including life-space mobility, were also associated with increased readmission risk. CONCLUSIONS: Functional impairments are robust predictors of hospital readmissions in older adults. Routine assessment of physical function during hospitalization can improve risk stratification and may support successful care transitions, particularly in older adults.