Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a common coronary artery anomaly associated with high mortality and may lead to sudden death if left unrecognized and untreated. This report describes an 8-year-old female who had cardiac murmur but with no clinical symptoms. Electrocardiogram (ECG) was normal, but echocardiography made the diagnosis of ALCAPA. Digital subtraction angiography (DSA) with cardiac catheterization angiography (CAG) confirmed the diagnosis, and finally, the patient received surgery. This case demonstrates that echocardiography is a sensitive and convenient technique for establishing the initial diagnosis of ALCAPA in both symptomatic and asymptomatic patients.