We describe a case of an 87-year-old human immunodeficiency virus (HIV)-negative man who developed a primary pleural lymphoma without any identifiable tumor mass associated with human herpesvirus 8 (HHV-8) infection. A large T-cell lymphoma was diagnosed based on morphologic, immunophenotypic, and molecular findings. The HHV-8 DNA sequences were detected using specific polymerase chain reaction amplification in the lymphomatous effusion. Study of the patient's serum confirmed the HHV-8 infection. This case report displays the characteristic features of HHV-8-related body cavity-based lymphoma/primary effusion lymphoma previously reported in HIV-seronegative patients, except that it is of T-cell origin. Whether this case may be included or not within the primary effusion lymphoma entity, the association of a pleural T-cell non-Hodgkin lymphoma with HHV-8 infection raises the question of the possible occurrence of T cells as the target of malignant transformation associated with HHV-8 infection.