The clinical literature in Huntington's disease (HD) suggests that unawareness of deficits is prevalent among HD patients. However, few studies have characterized unawareness of different types of impairment within this neuropsychiatric disorder. The purpose of the current study was to examine self-awareness of functioning across symptom domains in HD patients and to explore the association between impaired awareness and cognitive dysfunction. A total of 66 pairs of HD patients and collaterals of the patients completed symptom-rating measures regarding both the patients' and the collaterals' behavior. A subset of 19 patients also underwent neurological and neuropsychological assessments. The results indicated that patients lacked awareness across symptom domains (i.e., behavioral control, emotional control, activities of daily living), which was significantly greater for their perception of their own behavior than for their perception of their collateral's behavior. Exploratory analyses revealed associations between impaired self-awareness, global cognition, and deficits in executive functioning and memory. The current findings underscore the importance of examining different types of impaired awareness including both over- and underreporting of abilities. Future studies will benefit also from examining the association between awareness and cognition in larger samples.