Primary central nervous system lymphoma (PCNSL) is an aggressive form of non-Hodgkin lymphoma restricted to the central nervous system. Stereotactic biopsy is the gold-standard for diagnosis of PCNSL. Extent of disease evaluation for newly diagnosed PCNSL patients includes brain imaging, eye examination, cerebrospinal fluid assessment, body imaging, and bone marrow biopsy. Methotrexate-based chemotherapy is the standard induction for PCNSL patients. Optimal consolidation therapy for PCNSL has not been defined, with several options feasible, including chemotherapy, high-dose chemotherapy, and autologous stem cell transplantation or whole-brain radiation therapy. Optimal treatment for relapsed and refractory PCNSL has not been defined.