Primary brain lymphoma (PBL) is a rare disease, the study of which is based on small series and case reports. The AA review new cases of PBL not associated to immunodeficiency at the Portuguese Institute of Oncology of Porto since 1978. Five male patients were found with lymphoma primarily located in the brain, with aggressive histology, IE staging, detected by CAT, NMR or brain scintigraphy and with histologic material collected by stereotaxic biopsy (3 cases) or by craniotomy (2 cases). Three patients were in complete remission (25,5 and 1 year) and 2 were dead with a survival of 12 and 17 months. The cases and literature are discussed.