Background: Coronary artery fistula (CAF) is a rare lesion that was in 0.2-0.4 % of congenital heart disease. In childhood, most of patients have no symptoms. However, CAF may cause serious complications such as congestive heart failure, myocardial infarction and infectious endocarditis. We experienced 3 interesting cases with congenital CAF and discussed the management and treatment. CASE 1: A 4-years-old boy with no symptom was referred to our hospital for evaluation of a heart murmur found at 3 years of age. The diagnosis by echocardiography and angiography was the right CAF drained to the right ventricle. There were no coronary artery lesions. CASE 2: A 1-years-old, asymptomatic, boy who had diagnosed right CAF(RCA-RV)at the age of 4 days was referred to our hospital. The giant aneurysm was noticed by echo. CASE 3: A girl was found to have a heart murmur on routine examination at the age of 6 months and diagnosed the right CAF that was drained to the right atrium. There were no signs of cardiac failure, but when aged 17 months, echocardiography and angiography revealed that there was the giant aneurysm. Discussion: In present cases, we experienced that the aneurysm could enlarge progressively in short term in 2 patients. These lesions may raise sudden death in their later life, and should be cured early. Conclusion: Surgical correction has very low mortality and is curative, so early surgical closure was recommended. Case 2 & 3 were immediately intended to schedule of surgical closure.