Plasmablastic lymphoma is a rare subcategory of non-Hodgkin lymphoma frequently associated with human immunodeficiency virus. It is a large B-cell lymphoma that has a predilection for the oral cavity. Clinically, plasmablastic lymphoma may mislead to a diagnosis of Kaposi's sarcoma. When infected, plasmablastic lymphoma may mimic an odontogenic cellulitis. Epstein-Barr virus and human herpesvirus 8 are very often associated. Awareness of this entity can prevent misdiagnosis with nonlymphoid malignancies, notably Kaposi's sarcoma, because this lesion does not express the conventional B-cell markers. Unfortunately, as for other high-grade lymphomas in patients with acquired immunodeficiency syndrome (AIDS), the prognosis is poor. The case of a heterosexual 42-year-old man referred for a right hemifacial neoplasm is reported. Schlagwörter: Epstein-Barr virus, human herpesvirus 8, human immunodeficiency virus (HIV), non-Hodgkin lymphoma, plasmablastic lymphoma, oral cavity