Abstract： Objective To discuss the value of MSCT in diagnosis of left pulmonary artery sling (LPAS) with tracheobronchial anomaly.Methods MSCT was performed in 9 children with LPAS and tracheobronchial anomalies,CT findings were analyzed retrospectively. Results According to the Wells classification of LPAS,which includes two main types and two subtypes,there were 2 patients of type 1A,3 patients of type 1 B,2 patients of type 2A and 2 patients of type 2B.All of children had tracheobronchial stenosis.Local tracheobronchial stenosis was found in 4 patients ( all were type 1 ) and long tracheobronchial stenosis in 5 patients ( 1 patient with type 1 and 4 patients with type 2).Conclusions MSCT is an ideal imaging modality for simultaneously identifying LPAS and associated tracheobronchial anomalies.The Wells classification is very useful for operation planning.