Multiple myeloma is a monoclonal gammopathy with proliferation of plasma cells. Its form of presentation is hypercalcemia, osteolytic lesions, anemia and renal failure. The involvement of the central nervous system is rare. It occurs approximately in 1% of patients, whose diagnosis is made through the study of cerebrospinal fluid, with the presence of plasma cells. There is no specific treatment due to the low incidence. But there have been good results with intrathecal treatment.