We report an unusual case of endobronchial primary large B-cell Non Hodgkin Lymphoma in a HIV-infected patient in the course of effective Highly Active Antiretroviral Therapy (HAART). Diagnosis of large B-cell NHL was obtained by fibreoptic bronchoscopy (FOB) biopsies. Three cycles of R-CHOP chemotherapy (rituximab, vincristine, cyclophosphamide, hydroxydaunorubicin, prednisone) was performed and clinical and radiological remission was obtained after 3 cycles of therapy.