【目的】探讨小儿肺炎支原体肺炎合并肺不张采用纤维支气管镜下肺泡灌洗术诊断和治疗的效果。【方法】回顾性分析小儿肺炎支原体肺炎合并肺不张98例的临床资料,分析临床特征,肺泡灌洗液 MP-DNA 检测的阳性率,病变镜下表现以及临床治疗效果。【结果】小儿肺炎支原体肺炎合并肺不张年龄分布以>5岁且≤14岁年龄段最多。右中叶不张比例最高；肺泡灌洗液 MP-DNA 检测的阳性率86.7%,高于血清学 MP-IgM 的检测结果(P 5 years old and up to ≤14 years old took the most.The propor-tion of right middle lobe atelectasis was the highest.The positive rate of MP-DNA testing in BALF was 86.7%, which was higher than detection of serum MP-IgM(P <0.01).Under bronchoscopy,all cases were with bronchial mucosal edema,38 cases were with mucosal longitudinal folds,22 cases were with inflammatory stricture,and 5 cases were with mucus plug.All cases were treated with fiber bronchoscopic lavage,and 4 weeks after treatment, the complete recovery rate was 85.7%.intraoperative transient cyanosis of eight cases were relieved after symp-tomatic treatment.[Conclusion]The positive rate of MP-DNA detection in children with mycoplasma pneumoniae pneumonia combined with pulmonary atelectasis in children was higher than that of MP-IgM.Using fiber broncho-scope under alveolar lavage treatment may obtian higher recovery rate.