BACKGROUND: Apathy is a debilitating behavioral change in Huntington's disease (HD), but impulsivity in HD has not been well documented, and the co-occurrence of these behaviors in HD has not been investigated. OBJECTIVE: Our objective was to determine whether apathy and impulsivity co-occur in people with HD and their associations with quality of life. METHODS: Carriers of Huntington's gene expansion (premanifest to mild motor manifest disease; n = 42) along with healthy controls (n = 20) completed measures of apathy (Apathy Evaluation Scale and Apathy Motivation Index) and impulsivity (Barratt Impulsiveness Scale-11 and UPPS-P impulsivity scale), along with mood, cognition, clinical, and quality of life measures. Apathy and impulsivity measures were each reduced to a single metric per patient using principal component analysis. Correlations and multiple linear regression models determined associations between apathy and impulsivity and the potential influence of other covariates. RESULTS: Apathy and impulsivity were significantly correlated (r = 0.6, p