Human herpesvirus-6 (HHV-6) is largly disseminated in human population, which may relate to many diseases. Due to different methods previously used, the results of HHV-6 DNA detections in patients with leukemia are not identical. With a control-study, HHV-6 DNA in the blood cells from 38 cases, including 30 cases with acute myeloid leukemia and 8 cases with chronic myelogenous leukemia was detected by nested PCR. The results showed that HHV-6 DNA positive rate (63%) in patients with AML was lower than that in controls, whereas no significant difference between patients with CML (75%) and controls (92%) was shown. The clinical importance of HHV-6 infections in myelogenous leukemia should continue to be investigated later.