Aim of the work: this study aimed to assess the role of ECG gated multidetector computed tomography in detection and characterization of congenital heart diseases. Patients and method: this study was carried out in the Radiology Department of Ain Shams University Hospitals. A total of 30 patients presented with clinically/echocardiographically known to have congenital heart disease. They were 17(56.7%) females and 13 (43.3%) males. Their age was ranged from 3 days -18 year old. Results: Regarding the cardiac abnormalities, we found good agreement between Echo and ECG gated MDCT as regard cardiac abnormalities with kappa value measuring 0.771. Regarding great vessels anomalies, we found overall good agreement between Echo and MDCT where k measuring 0.790. As regard extracardiac findings, lung changes that were seen in MDCT only in form of lung consolidation in three cases (10%) and one case of unilateral lung hypoplasia (3.3 %). Conclusion: ECG gated MDCT is considered as an essential non-invasive diagnostic tool for the evaluation of congenital cardiac and extra cardiac great vessels. MDCT is complementary to the cardiac echocardiography especially in complex heart abnormalities.