Brucella spp. was isolated from blood cultures in a mean time of 3.1 days (range, 2-5) in seven cases of human brucellosis processed with the Isolator lysis-centrifugation system. Simultaneous BACTEC NR blood cultures in the same patients were positive in six, with a mean detection time of 20.6 days (range, 17-29). These data suggest a higher speed of recovery of Brucella spp. from blood specimens with the lysis-centrifugation procedure compared with the BACTEC NR system.