IgG4-related systemic disease (IgG4-RD) is characterized by an inflammatory reaction rich in IgG4-positive plasma cells, affecting multiple organs. This report describes a case who was diagnosed with IgG4-RD, having cerebral venous thrombosis and a subsequent acute ischemic stroke of undetermined cause. A 47-year-old woman presented with headache, visual disturbance and eyelid swelling and two years later she was admitted with acute attacks of mild left lower limb sensory-motor monoparesis. Indirect immunohistochemistry assay showed elevated level of IgG4, labeling neurons of the central nervous system, suggesting an immunological process possibly affecting vascular structures. Our experience suggests that IgG4-RD may be considered in patients with ischemic stroke and cerebral venous system involvement.