This is a descriptive, correlational study of the predictors of perceived cognitive functioning. The convenience sample of 728 nonhospitalized persons receiving health care for HIV/AIDS was recruited from seven sites in the United States. All measures were self-reported. Self-perception of cognitive functioning, the dependent variable, was composed of three items from the Medical Outcomes Study HIV scale: thinking, attention, and forgetfulness. Data related to age, gender, ethnicity, education, injection drug use, CD4 count, and length of time known to be HIV-positive were collected on a demographic questionnaire. The scale from the Sign and Symptom Checklist for Persons with HIV Disease was used to measure self-reported symptoms. Data were analyzed using hierarchical multiple regression analysis. Predictors of perception of cognitive functioning explained a total of 36.3% of the variance. Four blocks--person variables (1.5%) (age, gender, education, history of injection drug use), disease status (2.3%), symptom status (26.5%), and functional status (5.4%)--significantly contributed statistically to the total variance. Among those individuals who completed the questions related to depression (n = 450), 28% of the variance in cognitive functioning was explained by this variable. The findings in this multi-site study indicate that symptom status explained the largest amount of variance in perceived cognitive functioning. Early identification of cognitive impairment can result in appropriate clinical interventions in remediable conditions and in the improvement of quality of life.