Multiple sclerosis (MS) is a chronic neurodegenerative disorder often associated with cerebellar ataxia. Accurate assessment of ataxia is crucial for monitoring disease progression and guiding rehabilitation. The Scale for the Assessment and Rating of Ataxia (SARA) is a clinician-reported outcome measure (ClinRO) designed to evaluate ataxia severity. This study aimed to translate, culturally adapt, and validate the Italian version of SARA in individuals with MS. This study follows a cross-sectional design and was conducted at the Neurorehabilitation Unit of Sapienza University of Rome. The translation followed ISPOR and ISOQOL guidelines to ensure linguistic and cultural equivalence. Psychometric properties evaluation included internal consistency (Cronbach's alpha), test-retest reliability (intraclass correlation coefficient [ICC]), construct validity (correlation with Berg Balance Scale [BBS], Mini-Balance Evaluation Systems Test [Mini-BESTest], and Timed Up and Go [TUG] test), and cross-cultural validity. Seventy-five MS patients (EDSS ≤ 6.5) were recruited. The Italian SARA version demonstrated excellent internal consistency (Cronbach's alpha = 0.855) and test-retest reliability (ICC = 0.993). Strong negative correlations were found with BBS (r = -0.838, p <
0.001) and Mini-BESTest (r = -0.767, p <
0.001), supporting construct validity. Significant differences emerged based on age, employment status, and EDSS scores. The Italian SARA is a valid and reliable tool for assessing ataxia severity in MS. Its strong psychometric properties support its use in clinical and research settings. Future studies should explore its responsiveness to rehabilitation interventions.