The prevalence of anemia in HIV-infected persons has not been well characterized in the HAART era. In a single-center, retrospective study, anemia prevalence and risk factors, including use of HAART, were assessed in an ambulatory clinical cohort of 758 HIV-infected patients for the calendar year 2000. The relationships between anemia (hemoglobin level less than 12.5 g/dL) and demographic variables, antiretroviral treatment regimens, and disease markers were analyzed. Mean baseline patient characteristics were hemoglobin level, 13.7 +/- 1.9 g/dL; CD4+ cell count, 405 +/- 293/microL; and HIV RNA level, 77,841 +/- 148,394 copies/mL. Overall anemia prevalence was 30.3%. Multivariate logistic regression analysis demonstrated that anemia was associated with a CD4+ cell count below 50/microL, female sex, black race, a viral load above 100,000 copies/mL, zidovudine use, and older age. Severe anemia was less prevalent in this study population than in historical comparators; however, mild to moderate anemia rates remain high.