Objective:To explore the etiology and clinical features of multiple cystic lung disease(MCLD)in children. Methods:The clinical data of 25 cases of MCLD in Children’s Hospital Affiliated to Chongqing Medical University from March 2004 to December2012 were retrospectively analyzed. Results:(1)The causes of MCLD in children were expressed as follows:12 cases(48%) with bronchopulmonary dysplasia(BPD)

7 cases(28%)with Langerhans cell histiocytosis(LCH)

3 cases(12%)with idiopathic pulmonary fibrosis

and 3 case of unknown reason.(2)Clinical manifestations of respiratory systemwere expressed as follows:22 cases(88%)had tachypnea

16 cases(64%)had cough

15 cases(60%)had dyspnea. Extrapulmonary manifestations were various and specific:ear pus overflow in 3 cases(12%)

head mass in 2 cases(8%)

anemia in 6 cases(24%)

lymph nodes in 5 cases(20%)

hepatosplenomegaly in 7 cases(28%)

skin rash in 3 cases(12%)

clubbing in 1 case(4%).(3)Computed tomographyexamination was performed on 25 cases

and allwere showed MCLD.(4)Three cases of idiopathic pulmonary fibrosis(IPF)had pulmonary function tests

and the results suggested restrictive ventilatory defect. Conclusion:The common causes for children with MCLD in this study are BPD

LCH

IPF. The extra-pulmonary manifestations are various and specific and are important. Thoracic CT is an important tool for diagnosing MCLD