Purpose: This study aimed to retrospectively analyze the imaging features of an anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) in pediatric patients, with cardiac computed tomography (CT) and echocardiography. Materials and Methods: To define the precise location of ostium of the left coronary artery, we examined 9 patients using chest film, electrocardiogram, echocardiography, and cardiac CT 4 modalities, 2 of them also using cardiac MR and 1 of them using catheter cardiac angiography. Cardiac CT scan was performed in all 9 patients using a body size adapted low-dose protocol after bolus injection of intravenous nonionic contrast medium. Multiplane reconstruction, maximum intensity projection, and 3-dimensional coronary tree images were obtained for each patient. Two radiologists in consensus analyzed the cardiac CT findings for the origin of the anomalous coronary artery, course, and collateral vessels. The ALCAPA in these 9 patients was confirmed retrospectively by surgery. Results: Cardiac CT can distinguish the site of origin of the anomalous left coronary artery and variants: 2 patientswith inner ostium of the pulmonary trunk, 3 patients with left-sided ostium, 2 patients with posterior ostium, and 2 patients with sinus of the pulmonary root ostium; 1 patient combined with the right coronary artery arising from the left coronary sinus. Conclusions: Cardiac CT can provide fast and accurate depiction of complex coronary arteries, particularly in unstable and fragile patients with ALCAPA, and according to cardiac CT, surgical strategies can be decided. © 2015 Wolters Kluwer Health, Inc.