Objective To understand the status quo of living space in elderly patients after total knee arthroplasty （TKA） and analyze its influencing factors.Methods A convenient sampling method was adopted from December 2024 to February 2025 to survey 351 elderly patients who had undergone TKA for the first time and had been postoperative for more than 6 months.The general information questionnaires, the Chinese version of the Tampa Scale of Kinesiophobia-11 (TSK-11), the Self-Efficacy for Rehabilitation outcome Scale (SER), the Groningen Orthopedic Social Support Scale (GO-SSS), the 8-Item Ascertain Dementia (AD8), the Lower Extremity Functional Scale (LEFS), and the Chinese version of the Life Space Assessment (LSA-C) scale were used for the survey.Results The rate of living space limitation in elderly patients after TKA was 32.76%; logistic regression analysis showed that social participation, vision status, postoperative complications, self-efficacy for rehabilitation, orthopedic social support, and lower extremity function were the influencing factors of living space limitation in elderly patients after TKA (all P＜0.05).Conclusion The incidence of living space limitation in elderly patients after TKA is relatively high.Medical staff should pay attention to the living space status of elderly patients after TKA, and develop targeted intervention measures based on the relevant influencing factors to improve their postoperative living space level and thereby improve the quality of life after surgery.