To examine the relationship between cognitive impairment and desire for death in patients with advanced AIDS we evaluated 128 patients with advanced AIDS consecutively admitted to three long-term care facilities. Participants completed a clinical assessment that included a self-report measure of desire for hastened death in the medically ill (Schedule of Attitudes toward Hastened Death), three measures of cognitive functioning designed to screen for cognitive impairment (Dementia Rating Scale, Mini-Mental State Exam, HIV Dementia Scale), and other measures of physical and psychological functioning. Participants who were classified as cognitively impaired obtained significantly higher scores on the measure of desire for death than did patients without cognitive impairment. This modest association between cognitive impairment and desire for death remained significant even after controlling for the impact of depression on desire for death. Specific aspect of cognitive functioning such as memory and psychomotor coordination appeared to be more salient than executive functioning or abstract reasoning. Cognitive impairment appears to have a modest, but significant impact on patients' desire for hastened death. Aggressive treatment of cognitive symptoms in the terminally ill is necessary in order to disentangle the various factors that may drive end-of-life treatment decisions.