Corticosteroid has been used in adulthood refractory MPP with satisfactory efficacy. But there were few studies about the use of corticosteroid in children with refractory MPP. Lee KY et al indicated oral prednisolone of 1 mg/kg/ day for 1 week be useful for children with severe MPP. Akihiro T et al demonstrated that intravenously administered methylprednisolone at a dose of 30 mg/kg once daily for 3 consecutive days had an efficacious treatment for children with refractory MPP.But the methods of corticosteroid use, such as the dosage, administration route, duration of treatment have not been well understood. So in this study, we planned to investigate whether small doses of methylprednisolone pulse macrolide therapy can relieve symptoms,chest X-rays faster than macrolide alone therapy for refractory mycoplasma pneumoniae pneumonia in a prospective, open-label fashion.