Oral plasmablastic lymphoma is a rare malignancy that is associated with patients with HIV or other immunosuppression. This article describes a case of a patient with severe haemophilia A (<1% factor VIII) who had medically acquired HIV and hepatitis C, a CD4+ count of 192 cells/μL and a viral load of 33 200 copies/mL. The patient presented with a two-month history of a firm swelling around a lower molar. The tooth was removed and the surrounding tissue biopsied. The importance of obtaining an early definitive diagnosis and seeking adequate medical treatment is discussed.