Severe immunodeficiency is associated with reactivation of latent Epstein-Barr virus (EBV) that is manifested by virus replication. It is unknown whether EBV replication also occurs in the Hodgkin's disease (HD) tissue of patients infected with the human immunodeficiency virus (HIV). Therefore, we studied paraffin-embedded lymph nodes from 13 cases of HIV-associated HD to determine the latent or replicative state of EBV infection. All patients were seropositive HIV-infected men; additional clinical information was available for 12 patients. The risk factor(s) for HIV infection were homosexuality (n = 7), intravenous drug abuse (n = 2), homosexuality and intravenous drug abuse (n = 1), sexual promiscuity (n = 1), or hemophilia (n = 1). Advanced clinical stage and B symptoms were common at the time of initial diagnosis of HD. The histological subtype of Hodgkin's disease was universally mixed cellularity, except for a single case classified as nodular sclerosis. Seven cases exhibited foci of relative lymphoid depletion. Five cases contained foci of necrosis. Reed-Sternberg (RS) cells and RS cell variants were positive for CD30/BerH2 and negative for CD45/LCA, CD45RO/UCHL1, and CD20/L26 in all cases. Tumor cells were positive for CD15/LeuM1 in seven cases. In all 13 cases, RS cells and RS cell variants were infected by latent EBV as shown by in situ hybridization to EBV-encoded ribonucleic acid (EBER1). In 12 of 13 cases neoplastic cells coexpressed EBV latent membrane protein 1 (LMP1). EBV replication was examined by two different methods: immunohistochemistry to identify EBV-encoded BZLF1 protein and in situ hybridization to detect EBV BHLF1 transcripts. No positivity in RS or RS cell variants was detected with either assay of EBV replication (95% confidence interval [CI] = 0% to 23%). The findings confirm that EBV is detected more frequently in HIV-associated HD when compared with immunocompetent patients with HD. The findings also suggest that EBV is tightly latent within RS and RS cell variants of HIV-associated HD. It appears that factors other than host immune status are important in maintaining EBV latency in HIV-associated HD.