According to Jain et al[20], CD5 positivity is classically associated with a poor prognostic factor, having female preponderance, more bone marrow involvement, higher LDH levels, B symptoms on presentation, and Ann Arbor stage 3 to 4 on diagnosis.[21] In this current case, based on the morphology and immunophenotype, we present a case of a young male patient with a diagnosis of AIDS-related diffuse large B cell lymphoma, CD5-positive, with a high LDH level and stage IV Ann Arbor at presentation. This evidence concerns the gene CD5 and diffuse large B-cell lymphoma.