Purpose: Neuropsychological assessments serve as useful tools for measuring and tracking cognitive impairment in individuals with neurological disorders. However, a full neuropsychological battery is not feasible for most routine medical visits. Since physicians are expected to assess cognition in a concise—yet, comprehensive—manner, brief screening measures of global cognitive function are routinely used in clinical settings. The most frequently used screening instrument—Mini Mental State Exam (MMSE)—has been criticized for a shortage of items assessing executive functioning/attention. These limitations are of increased concern when assessing clinical populations characterized by frontostriatal dysfunction, such as Huntington’s disease (HD) patients. The Montreal Cognitive Assessment (MoCA) encompasses a broader range of cognitive-specific items and has demonstrated high specificity and sensitivity. The purpose of the current study is to compare the longitudinal utility of the MMSE and MoCA in HD. Participants/Subjects: Archival data for this study were sourced from the University of California, San Diego (UCSD) HD Clinical Research Center. A total of 117 HD patients were followed across 5.09 years (SD = 3.20) and completed 6.69 (SD = 3.61) testing visits, on average. Method: The MoCA and MMSE were administered and scored using standardized procedures. A bivariate multilevel model was used to examine the average change in global cognitive functioning across time determined by (1) MoCA scores, (2) MMSE scores, and (3) the difference between the estimates of the two cognitive instruments. Results: On average, individuals with HD declined by .47 points on the MoCA and .54 points on the MMSE per year. Age at baseline and years of education did not predict rate of decline. However, education level did have a significant effect on baseline test scores, such that, more years of education corresponded to higher scores at baseline. Finally, there was no evidence to suggest a difference between the slopes of the MoCA and MMSE. Conclusions: These results suggest that the MoCA and MMSE do not differ in their longitudinal evaluation of cognitive functioning in HD patients. This research may be useful for informing physicians in clinical settings and future clinical trials in need of brief cognitive measures.