Background <p>Resilience, the ability to recover from adversity, plays a pivotal role in promoting positive health outcomes, particularly in older adults facing age-related challenges. Understanding and assessing resilience can help healthcare professionals identify those who are more likely to recover successfully from illness or injury and tailor interventions accordingly. This study examined the psychometric properties of the Farsi version of the Brief Resilience Scale (BRS) among older adults in Tehran, evaluating its validity and reliability in this population.</p> Methods <p>This study followed a rigorous translation and back-translation process to ensure the cultural and linguistic accuracy of the BRS. Face validity was assessed through qualitative interviews with 20 older adults, and content validity was evaluated based on feedback from 11 experts. A total of 330 older adults from parks across five districts in Tehran were recruited using convenience sampling. Construct validity was examined using Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). Convergent validity was assessed through correlations with the SF-12 and Zimet’s social support scale, along with the Average Variance Extracted (AVE), while divergent validity was evaluated using the Hospital Anxiety and Depression Scale (HADS). Reliability was determined through internal consistency (Cronbach’s alpha, McDonald’s omega, and Composite Reliability) and test–retest stability over a two-week interval (ICC).</p> Results <p>Approximately half of the participants were male, with a mean age of 69.5 ± 7.2 years. Both face and content validity of the scale were confirmed, with high CVI and CVR scores. Exploratory Factor Analysis (EFA) indicated an adequate sample size (KMO = 0.754) and significant correlations among items. Confirmatory Factor Analysis (CFA) demonstrated that a modified single-factor model provided the best fit (AIC = 539.47, SRMR = 0.019, RMSEA = 0.042, TLI = 0.988, CFI = 0.994). Convergent validity was supported by significant positive correlations between the BRS and both the SF-12 (r = 0.394) and Zimet’s social support scale (r = 0.304) (P &lt; 0.001), as well as by the Average Variance Extracted (AVE). Divergent validity was established through significant negative correlations with HADS anxiety (r = -0.420) and depression (r = -0.329) scores (P &lt; 0.001). Internal consistency was excellent (Cronbach’s alpha = 0.84, ω = 0.86, Composite Reliability = 0.86), and test–retest reliability over a two-week interval was high (ICC = 0.96)</p> Conclusion <p>The Farsi version of the BRS proved to be a valid and reliable tool for assessing resilience in Iranian older adults. Its strong psychometric properties make it an effective instrument for use in both research and clinical settings. Given the high prevalence of age-related challenges in this population, integrating resilience assessments into care plans may help improve overall health outcomes. Future studies should explore the use of the BRS in diverse populations and its potential role in resilience-based interventions.</p>