Plasmablastic lymphoma (PBL) is a diffuse large B-cell lymphoma, a new entity, the incidence of which is increasing, predominantly in the oral cavity of immunocompromised patients, most of whom are infected with human immunodeficiency virus (HIV); only four cases have been reported in non-HIV-infected patients. This report details two cases of PBL of the oral cavity in immunocompetent patients. In both cases, the tumour manifested as a solitary, firm mandibular swelling with dense infiltration of plasma and blastoid cells in the stroma with strong positivity for CD 138 and negativity for CD 20. The patients received radiotherapy and chemotherapy, which resulted in complete remission of the lesion. This is the only case report of two cases of PBL in the oral cavity in immunocompetent patients in which both patients received treatment and showed complete remission of the lesion.