ObjectiveTo analyze the path relationships among influencing factors for kinesiophobia in knee arthroplasty patients through a structural equation model. BackgroundThe occurrence of kinesiophobia significantly impacts the rehabilitation process of knee arthroplasty patients. However, there is still a need to determine factors that contribute to reducing kinesiophobia. DesignA cross-sectional study was conducted and reported following the STROBE guideline. MethodsBetween February 2022 to October 2022, 162 total knee arthroplasty (TKA) patients and 81 unicompartmental knee arthroplasty (UKA) patients completed a survey. A structural equation modeling (SEM) approach was utilized to analyze the relationships between kinesiophobia and influencing factors (social support, pain resilience, and rehabilitation self-efficacy). Furthermore, multi-group SEM analysis was conducted to examine whether the model equally fitted patients in different types of knee arthroplasty. ResultsThe direct negative effects of rehabilitation self-efficacy (β = −0.535) and pain resilience (β = −0.293) on kinesiophobia were observed. The mediating effect (β = −0.183) of pain resilience and rehabilitation self-efficacy between social support and kinesiophobia was also significant. The SEM model achieved an acceptable model fit (χ2 = 35.656, RMSEA = 0.031, χ2/df = 1.230, GFI = 0.972, NFI = 0.982, IFI = 0.997, CFI = 0.996). In multicohort analysis, no significant differences were observed among knee arthroplasties (TKA, UKA) (Δχ2 = 4.213, p = 0.648). ConclusionsSatisfactory social support enhances pain resilience and rehabilitation self-efficacy, so as to reduce kinesiophobia. Future interventions that directly target the assessment and management of kinesiophobia, available social support may help reduce kinesiophobia, and pain resilience and rehabilitation self-efficacy may be critical factors in managing kinesiophobia. Relevance to Clinical PracticeReducing kinesiophobia in knee arthroplasty patients requires satisfactory social support, pain resilience, and rehabilitation self-efficacy. Therefore, healthcare organizations may implement initiatives to reduce kinesiophobia by taking these factors into account.