Rheumatoid vasculitis (RV) causes various complications in the heart, lungs, kidneys, and nerves that require intensive treatment. Rapid RV-related peripheral nerve involvement progression is critical and requires prompt treatment. We report the case of a 73-year-old female with RV, with a chief complaint of difficulty walking without any infectious symptoms for several months. We diagnosed Guillain-Barré syndrome (GBS) accompanied by RV and treated the patient with intravenous immunoglobulin and cyclophosphamide. Previous impairments of activities of daily living (ADLs) were resolved. Diagnosing the neurological manifestations of RV and GBS in older patients with an active RV is challenging because of the various patterns of the progression. For effective management, considering both diseases and implementing immunosuppressive and modulatory treatments is critical to stop the progression of neurological symptoms and prevent the deterioration of ADLs.