We report on a case of refractory myasthenia gravis that was managed by using intravenous immunoglobulin. A 35-year-old Chinese woman with malignant thymoma-associated myasthenia gravis was treated by total thymectomy, followed by chemotherapy. Thirty months later, she developed respiratory failure and required mechanical ventilation for 2 months. A course of intravenous immunoglobulin was given and her condition improved significantly. Two weeks later, the patient became ambulatory, was prescribed oral pyridostigmine, and was discharged home.