Background and objectives: Congenital thoracic vascular anomalies are associated with great risk of mortality and morbidity. Their growing incidence is assumed to originate mainly from the increased accuracy of the diagnostic methods used. Although classic angiography is considered the gold standard diagnostic method, various diagnostic methods have been proposed. Dual-source computed tomography (DSCT) angiography is the most recently introduced CT technology with confirmed diagnostic accuracy in adult population. The present study is aimed to determine the diagnostic value of DSCT in children with congenital thoracic vascular anomalies compared with the gold standard CTA. Materials and methods: The present cross-sectional study investigated the diagnostic accuracy of DSCT in 100 pediatric patients who referred to Shahid Rajaie Heart Center with congenital anomaly of major thoracic vessels and underwent DSCT and angiography from March 2011 to September 2014. DSCT images were reviewed by one radiologist to confirm the accuracy of reports. Next, parameters of diagnostic value of these methods were compared using IBM SPSS version 22. Results: A total of 142 cardiovascular anomalies were diagnosed by angiography. The diagnostic accuracy of DSCT was 97.1%, considering 2 cases of left superior vena cava and 2 patent ductus arteriosus missed by DSCT among the 142 anomalies diagnosed by angiography. DSCT also provided important additional findings (n = 26) which were not reported by angiography. Conclusion: DSCT is a highly accurate diagnostic method for detecting congenital vascular anomalies, obviating the need for invasive modalities.