BACKGROUND The goals of this study were: to compare echocardiogram and 64-multislice spiral computed tomography (64-MSCT) in diagnosing pediatric congenital heart disease; to determine the significance of ECHO for diagnosing congenital heart disease; and to identify the appropriate diagnosis for congenital heart disease through combined use of 64-MSCT and ECHO. MATERIAL AND METHODS Thirty patients underwent both ECHO and 64-MSCT diagnoses before their surgeries. Imaging from ECHO and 64-MSCT were analyzed by 4 specialists. The diagnostic accuracy and kappa value of ECHO and 64-MSCT were evaluated based on the operation results. The accuracy of the 2 methods was evaluated using the McNemar χ² test. RESULTS We confirmed 138 malformations in 30 children by surgery. The diagnostic accuracy of ECHO and 64-MSCT was 98.40% and 96.20%, respectively, with a significant difference between the 2 results (χ²=6.404, P=0.011). We compared prognosis accuracy and uniformity on 3 types of congenital heart disease (cardiac malformation, heart-large vascular connecting malformation, and large vascular malformation): 56 cardiac malformations were confirmed by surgery, in which the diagnostic accuracy of ECHO and 64-MSCT was 99.50% and 94.80%, respectively. (χ²=8.578, P=0.034); 31 heart-large vascular connecting malformations were confirmed by surgery, in which the diagnostic accuracy of ECHO and 64-MSCT was 99.00% and 95.42% (χ²=6.779, P=0.009); and 51 vascular malformations were confirmed, in which the diagnostic accuracy of ECHO and 64-MSCT was 96.30% and 98.30% (χ²=1.806, P=0.179). CONCLUSIONS ECHO is more effective than 64-MSCT in preoperative diagnosis of congenital heart disease, especially for children.