Though pediatric-onset systemic lupus erythematosus (SLE) is at high risk of coronary artery involvement, coronary artery dilation appears to be a rare characteristic of pediatric-onset SLE. In this article, we described 1 pediatric-onset SLE patient with coronary artery dilation at the diagnosis of SLE, in order to better diagnose and manage this cardiac complication of SLE in children.A 13-year-old boy was admitted in hospital for daily fevers with the highest temperature of 39.2°C over 10 days, with rash, non-exudative conjunctivitis, cervical adenopathy, knee, and ankle arthralgi. The result of echocardiogram implicated coronary artery dilation and aortic regurgitation. Further laboratory tests showed: Coomb's test (+), decreased C3 complement. The results of immunologic tests were only to find ANA (+) with titer 1:3200, ds-DNA (+).This patient was diagnosed as SLE complicated with coronary artery dilation.The patient was treated with intravenous methylprednisolone pulse therapy. He was discharged home on prednisone maintain treatment.As soon as treatment, his temperature returned to normal, with recovery of rash, conjunctivitis, knee, and ankle arthralgi. However, the echocardiogram of this patient after 3 months also had dilation of left coronary artery (LCA) and right coronary artery (RCA).Cardiac complication can occur during the entire course of SLE, suggesting that routine echocardiogram surveillance may be necessary for all SLE patients to prevent morbidity and mortality from cardiovascular events.