A retrospective analysis of 32 patients with primary malignant lymphoma of the central nervous system (CNS) diagnosed between 1976 and 1989 investigated treatment results and recurrence patterns. All patients showed either complete or partial regression of the tumor after initial treatment, mainly radiation therapy with adjuvant chemotherapy. The mean dose of whole-brain irradiation was 40.9 Gy and that of booster was 14.4 Gy. Most patients had tumor recurrence. The median time to recurrence from completion of the treatment was 5 months. The 1- and 5-year survival rates were 50.0 and 17.7%, respectively, and the overall median survival time was 11 months. Most tumors had multiple recurrences at the primary site and other regions of the CNS, and tended to recur in the periventricular region and the cerebrospinal fluid space. Spinal metastasis occurred in five cases. The importance of good control of the primary lesion and active maintenance therapy for the whole CNS is emphasized.