Eleven patients with primary lymphoma of the central nervous system were seen in the King Faisal Specialist Hospital and Research Centre, Saudi Arabia, between 1986 and 1992. None had previously received immunosuppressive therapy. All cases were confirmed by biopsy and histopathological studies. Of the eleven patients, six had debulking of the tumour, seven received radiation therapy and six received chemotherapy. This report confirms the very poor prognosis for patients with primary lymphoma of the central nervous system, with only a few long-term survivors.