Plasmablastic lymphoma (PBL) is a B-cellYderived lymphoma that is described as a subtype of the diffuse large B-cell lymphoma, commonly seen in patients with human immunodeficiency virus infection. The oral cavity is the first site of presentation with local invasion to the palate and the jaw and rapid dissemination to extraoral sites. The characteristic immunophenotype include the presence of plasma cell markers VS38c and CD138. Epstein-Barr virus and human herpes virus type-8 are strongly associated with the pathogenesis of oral PBL.Here, we describe a case of PBL of the oral cavity in a 55-year-old woman who was only treated with HAART and improved with a full remission of the neoplasm, which is probably related with a good control of the immunological and virological status associated with the highly active antiretroviral therapy.