The relationship between bacteremia and mortality was studied in 5882 burn patients consecutively admitted to one burn center between 1959 and 1983. Among 5877 patients with adequate data, 1481 had one or more positive blood cultures; 1529 patients died. A predictor of mortality was developed, based on data from the 4396 patients without positive blood cultures, and used to assign a discrete probability of death in the absence of bacteremia to all the patients. Comparisons were then made between observed and predicted mortality in subsets of patients with bacteremia due to enteric organisms, Pseudomonas species, gram-positive organisms, or yeastlike organisms, or without bacteremia. These comparisons indicate significantly increased mortality in patients with gram-negative bacteremia, an equivocal increase in patients with blood cultures positive for yeastlike organisms, and no increase attributable to gram-positive bacteremia.