This study examined how awareness of diagnostic label impacted self-reported quality of life (QOL) in persons with varying degrees of cognitive impairment. Older adults (n = 259) with normal cognition, Mild Cognitive Impairment (MCI), or mild Alzheimer's disease dementia (AD) completed tests of cognition and self-report questionnaires that assessed diagnosis awareness and multiple domains of QOL: cognitive problems, activities of daily living, physical functioning, mental wellbeing, and perceptions of one's daily life. We compared measures of QOL by cognitive performance, diagnosis awareness, and diagnostic group. Persons with MCI or AD who were aware of their diagnosis reported lower average satisfaction with daily life (QOL-AD), basic functioning (BADL Scale), and physical wellbeing (SF-12 PCS), and more difficulties in daily life (DEM-QOL) than those who were unaware (all p ≤ .007). Controlling for gender, those expecting their condition to worsen over time reported greater depression (GDS), higher stress (PSS), lower quality of daily life (QOL-AD, DEM-QOL), and more cognitive difficulties (CDS) compared to others (all p < .05). Persons aware of their diagnostic label-either MCI or AD-and its prognosis report lower QOL than those unaware of these facts about themselves. These relationships are independent of the severity of cognitive impairment.