The increasing global burden of dementia demonstrates the necessity for cognitive screening tools that rely less on language, culture, and education. The Rowland Universal Dementia Assessment Scale (RUDAS) was developed to address these limitations and has shown promising results in culturally diverse populations. The study examined the diagnostic accuracy of the Persian version of RUDAS in older Iranian adults with Alzheimer’s disease (AD). This case-control diagnostic accuracy study included 120 Persian-speaking older adults aged 65 to 85 years, comprising 60 with clinically diagnosed Alzheimer's disease and 60 cognitively healthy controls with comparable age and gender distribution. Participants were recruited from Tehran and northern Iran. Participants completed the Persian RUDAS, administered by assessors blinded to clinical diagnosis. Discriminant analysis was used to calculate the diagnostic indices and estimate the optimal cut-off point. At the cut-off score of ≤22, the Persian RUDAS demonstrated a sensitivity of 73.3% and a specificity of 90.0%. Positive and negative predictive values were 88.0% and 77.1%, respectively, with an overall diagnostic accuracy of 81.7%. Compared with controls, participants with AD performed significantly worse on body orientation, praxis, visuospatial drawing, memory recall, and verbal fluency, while no significant difference was observed in the judgment subscale. Findings from this study suggest preliminary evidence for the discriminative power of the Persian RUDAS towards clinically diagnosed Alzheimer's disease vs. cognitively healthy older adults in our studied population; Given its relatively limited dependence on language and educational background, RUDAS may be a useful screening instrument in culturally and educationally diverse populations.