Objective To analyse the clinical effect of methicillin-resistant staphylococcus aureus(MRSA) necrotizing pneumonia in children. Method A retrospective analysis was performed based on the clinical records,laboratory data and treatment effects which were collected from 12 cases with CA-MRSA necrotizing pneumonia. Results Of the 12 cases,5 cases were male and 7 female.The median age was 23 months (8 months ~3 years old) and they were healthy before admission.They were febril for 12~ 36 days and hospital day was 28 ~70 days.The general condition of all cases were poor,all had high fever and cough.Dyspnea was found in eight children.Fine rales were found on 10 cases.Sighs of pleural effusion were discovered by physical examination and chest X-ray.During the course of admission,2 children complicated with deep soft tissue abscess,2 cases complicated with staphylococcus scalded skin syndrome and the other complicated with sepsis syndrome.WBC count was (14.8~42.36)×10⁹/L and neutruophil was 78.8%~91.9% in peripheral blood routine test.Erythrocyte sedimentation rate was 52~114 mm/h and C-reactive protein was 68~140 mg/L.The pleural effusion biochemistry and routine test revealed a WBC count of (5 800~12 560)×10⁶/L,protein of 35~60 g/L.Pleural effusion culture and (or) blood culture in all cases was positive for MRSA.Chest CT revealed high density lesions in the area of lobar consolicated were found a week later.All cases were treated with vancomycin.After a followed up of more than 6 months,chest CT showed that almost lesions in lungs recovered during 6 months.No cases received pneumonectomy. Conclusions MRSA necrotizing pneumonia is more common in children younger than 3 years old.Pathogenesis of acute and rapid progress,clinically characterized by high fever,coughing and lung tissue necrosis.If diagnosed and treated promptly,the prognosis of MRSA necrotizing pneumonia is relatively well.