Objective To investigate the causes,clinical characteristics and treatment in newborns with air leak syndrome. Methods A retrospective case-control study was conducted. 33 newborns with air leak syndrome from January,2014 to January,2017 and 33 control cases,who born in the same period,were randomly selected with comparable gestational age and birth weight. The occurrence,type and treatment of air leak syndrome were retrospectively analyzed. Results The incidence of air leak syndrome increased year by year....