In the last decades new approaches to the diagnosis and treatment of Hodgkin's Disease (HD) have contributed to improved rates of survival and cure but the pathogenesis of the disease still remains unknown. Data have been collected suggesting a relationship between viral infections and HD. HD patients with evidence of Epstein-Barr virus genomes in their affected tissues have been recently reported. Human Herpes Virus six (HHV-6) is a newly isolated virus, derived from patients with lymphoproliferative disorders. In order to investigate the possible role of this virus in the pathogenesis of HD we looked for a specific segment of HHV-6 genome by means of the polymerase chain reaction (PCR) in tissue samples obtained from peripheral blood and lymphnodes in HD patients: one clearly positive case has been identified. This result is the first indication of HHV-6 sequences associated with a case of HD and raises the possibility that this virus might be involved in the pathogenesis of this lymphoproliferative disorder. The relationship between HHV-6 and HD therefore warrants further investigation.