Objective To examine the role of echocardiography in diagnosing and following-up the coronary arterial lesion in Kawasaki disease.Methods 259 cases of Kawasaki disease were detected by echocardiography. 97 cases of them were followed-up.Results Among them 48 cases were found to have coronary arterial lesions(18.5%), 90% presented evidence of coronary arterial lesion in the first-three-week illness. The lesion of LCA occured more common than RCA. The followed-up result reveals an easier recovery of mild dilatation farmation. 2 cases of coronary arterial aneurysm remain persistent.The inside diameter of arterial aneurysm was an important agent of prognosis.Conclusions Echocardiography is the most useful noninvasive technique to detect coronary arterial lesion.