Patients with multifocal motor neuropathy (MMN) respond to intravenous immune globulin (IVIg) and cyclophosphamide, although the benefit is not sustained. High-dose cyclophosphamide can induce a remission in patients with autoimmune diseases, including chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We describe a patient with refractory MMN who improved with high-dose cyclophosphamide (50 mg/kg for 4 days) without stem cell rescue. Following treatment she discontinued IVIg. At a 6-month examination, her strength had improved and she had regained the ability to write. High-dose cyclophosphamide may be a successful treatment for patients with MMN refractory to other therapies.