Meningeal lymphomatosis (ML) as the first manifestation of a splenic marginal zone lymphoma (SMZL) is rare. The descriptions of only 2 cases with this complication, one of which had ML as the first manifestation, have been published to date. We describe a 53-year-old man, an ex-smoker, who presented with transitory episodes of bilateral loss of visual acuity. On examination, only papilledema and splenomegalia were observed. The hemogram showed a predominance of lymphocytes with a villous morphology. Cytochemical staining and an immunophenotypic analysis revealed a positive reaction to tartrate-sensitive acid phosphatase and B-lineage markers (CD19+, CD20+, CD79b+, surface immunoglobulin 3 expression, immunoglobulin D+, CD5-, CD23-, CD10-, CD25-, CD103-, and CD11c-). Magnetic resonance imaging of the brain showed tumoral infiltration in both optic nerves and in the cervicodorsal meninges. The cerebrospinal fluid examination revealed significant pleocytosis, and all lymphocytes had a phenotype identical to that of the peripheral blood, confirming the presence of ML. The bone marrow section also showed lymphocytes with an immunophenotype identical to that of the peripheral blood.A splenectomy confirmed the SMZL diagnosis. Treatment with corticosteroids and intrathecal chemotherapy was administrated; however, the response was not good, and the patient died. In this report, we discuss the other 2 cases and ML in B-cell chronic lymphoproliferative disorders.