To evaluate the impact of older age (> 50 years old) on survival in late-stage human immunodeficiency virus (HIV) disease, the authors analyzed 846 HIV-infected patients at the San Francisco Veterans Affairs Medical Center from 1987 to 1992. The median age was 42 years with 171 (20.2%) subjects aged 50 or more years. Survival was measured from the date of initial lymphocyte testing (median CD4 count, 223 cells/mm3) until death or censoring. Compared with those aged less than 40 years, and after multivariate proportional hazards adjustment for other significant determinants of survival (CD4 percentage, CD8 count, hematocrit, and prior acquired immunodeficiency syndrome diagnosis), there was no difference in survival for those aged 40-49 years, but there was a trend toward decreased survival in those aged 50-59 years (relative hazard = 1.32, 95% confidence interval 0.90-1.94) and in those aged 60 or more years (relative hazard = 1.56, 95% confidence interval 0.99-2.46). The impact of older age on mortality in HIV disease is, however, less than the impact of age on overall mortality in the United States. Accordingly, while older HIV-infected patients do have a somewhat poorer survival, this risk need not be too highly emphasized in individual patients; older patients deserve aggressive management.