Few studies have indicated the efficacy of plasmapheresis in children with multiple sclerosis (MS). We report a 10-year-old girl with MS who was successfully treated with plasmapheresis. She experienced the first episode (vomiting and unconsciousness) at the age of eight years. After two years and six months remission period, she had a relapse with left hemiplegia. Her symptoms did not respond to high-dose intravenous methylprednisolone or immunoglobulin therapies, and rapidly deteriorated. After bulbar palsy was observed, plasmapheresis (total : every two days, seven times) was initiated at the 17th day during the relapse. Neurological symptoms improved remarkably after the second trial of plasmapheresis. There were no complications associated with plasmapheresis. Plasmapheresis may be effective as an additional therapy for exacerbation of acute neurological symptoms in children with MS.